A good question...
For me it was never about an "identity" though. I guess it was the internet first that convinced me that a zoophile community was the place to be (it was not, though). When I first realized that being sexually attracted towards animals wasn't common but rather uncommon, rare or even unique among all the people I knew, I didn't feel like I was left out or anything. Maybe this is, how exclusive zoos feel, but I never was exclusive. I liked people too (and still do), it was just one of many sexual interests I had. So, there was an aspect I couldn't share with others, no big deal.
When I got on the web, I didn't even know about zoophiles or anything. I searched (not googled, as google as a search engine didn't exist back then) for something I was interested in: "Dolphin Sex". Actually I was searching for mating footage, but my english language skills weren't as good as they are now, so I really didn't know the word for "mating" back then. I found a message board for zoophiles instead and after looking up what this word meant I joined. Of course I never found what I was looking for (at least for that time being) but found something I thought might be even more valuable: People to talk to about this very subject or interest.
Before, I only knew the word "sodomite" which was always used in a deragotary sense. I didn't even knew it also included anal sex and being gay as well, I thought it was used exclusively for zoophiles. Especially practicing zoophiles (bestialists). The new word I found sounded less dire, so I adopted it for me. I guess this might be considered an "identity". I, however, didn't feel like it was one.
Zoophiles are people who are sexually attracted towards animals. This described me perfectly, even if only partially, so this word was fine. I guess the worse part was, that the "identity" aspect was also quite important to many zoos of the late 1990s and the early 2000nds. Because they developed an ideology that survived to this day, an ideology I don't subscribe to.
The ideology is, that "zoophilia" isn't what the dictionary says that it is, one of many paraphilias from a long list of paraphilias a human might develop, but instead to mean "loving animals" (and nothing more) while people having sex with animals were looked down by the "pure" zoophiles and called "filthy bestialists" (or sometimes also "beastialists" and shortened to "beasties"). Beasties bad, zoophiles good. That was what they believed in.
Despite they couldn't deny that they also had sexual interests, but they were somehow more "pure" than those of beasties. Also they upheld the Z.E.T.A. principles that were conceived by a zoophile usenet (?) group somewhen in the 90s, if I wasn't mistaken. The rules of those principles were simple and kind of common sense. In fact, they always should have been common sense, so much so, that I was worried what kind of community I must have found that still needed to be told how to properly treat animals.
Anyway, while the Z.E.T.A. principles weren't bad in any way, they certainly became a hollow identity for some people. People usually used those principles when debating the outside world to show how much more civilized they were when confronted with terms like "chicken/goat fucker", but internally they didn't care much about those principles at all. The principles explicitely speak out against animal abuse and animal exploitation, especially when zoo porn is involved.
The people usually hiding behind Z.E.T.A. and using it as a shield were people who were openly promoting fence-hopping and other kind of trespassing, justifying it with having no access to animals any other way and needing animals in their life, even if it's not their own, they were sharing abusive porn, promoting it even, were openly looking for sex dates with pets or other animal in the care of other zoophiles and cared little to none about the wellbeing of animals, let alone if the animals in question even wanted to have sex in the first place.
So abusive practices like binding an animal to a fence-post were discussed or like wearing rain boots, where you could put the hindlegs of said animals into the rain boots with you, so they couldn't escape your sexual assault and the likes. They never cared about bonding with the animals, they never cared about "consent", they only cared about getting their kick. Zoophilia as a fetish might as well have applied well to these people.
Realizing this my respect for the Z.E.T.A. principles vanished, I thought for some time that they were a farce, before learning that they were in fact proper guidelines from a caring community that were horribly misused by this community back then and I learned to cut my losses and to leave them behind. Remember, when I found them, I was looking for mating footage. I wanted to experience animals doing natural things to each other, I wanted to experience their bliss at the height of climax, I never was too much interested in human x animal stuff in the first place.
For the next quarter of a century I looked for communities that would more align with my own interests, just to realize those might not exist. You know, finding animal mating material to fap to. Also genital closeups. Pretty much anything, where the human involvement ended with triggering the camera to take the picture or video. It certainly didn't help that I'm also into many species the typical zoo isn't into: Small critters and exotic animals. Most zoos are just into dogs and horses and into farm animals, anything that's convenient and easy to come by, while I was never into animals based on availability, but based on aesthetics I liked the most.
The closest I ever got to find "my people" were furry "feral" communities. Because when you deal with zoos, you usually deal with people being into fucking animals (or getting fucked BY animals). You usually don't run that often into people who are merely into animals without all the human sex stuff attached to it. But those exist as well, as I am one of those.
You may remember the line "You and me, baby, ain't nothin' but mammals, So let's do it like they do on the Discovery Channel" from the song "Bad Touch" by the "Bloodhound Gang"? Yeah, there are people who just watch nature documentaries, get aroused by what they see, deal with their hornyness and that's it. Like I said, I'm one of them. That's why I consider myself being a "zoophile". Not due to identity reasons, but because it aligns with the official definition of being a zoophile: Being sexually attracted towards animals, even if it's not an exclusive attraction.
However time and time again I ran into communities that were trapped between being delusional (convincing themselves that zoophilia really meant nothing but love and violently rejecting the official definition the outside world uses (you see that often enough in this very forum)), and between people who were nothing more than animal abusers (something the zoo community of old I once was part of called "beasties", which isn't really fair, because "bestiality" truely only means to have sex with an animal, nothing more, nothing less).
Yet, to this day you will find people peddling this "love" angle, even if no outside (and certainly not haters) ever buys into it, while on the other hand you'll find people with horrible anatomical knowledge who intend to punish a sitting dog for the tip of their penis sticking out of their sheath, because there is a bone inside, which they don't "believe" in. We truely live in magical times where facts cease to be facts if you just not believe in them really hard enough. And there's also abusers who openly asked me how to train their castrated dog who lost his libido with his balls to have sex with him, while I was debating a friend of mine, who just accused zoos of doing so, that this wasn't the case at all with zoos. The timing couldn't have been better. It really just broke my heart.
So, today, I really try to put a distance between myself and zoo "communities", as they certainly represent an "identity" I never had and never will have. I'm a zoophile in name only (because I don't run from the truth), but I'm not really compatible with what other zoos are into. I don't have the urge to fuck animals, even if I could imagine (and fantasize about) doing so. I admit, there's a certain bitterness lingering, but it isn't entirely aimed at the abusers of the past and communities I've been a part of back then, it's also aimed at myself for wasting decades trying to "find my people", when I could have realized sooner that they either didn't exist, or are just too rare to ever be found among larger, more broader defined communities.
That said, I also don't align my life to accomodate for having pets or a farm and I certainly won't be getting any pet until I can make sure I can care well for it first. I know a furry who said "I only trust people with pets, because they show they can be trusted as they care for others than themselves." and I always disagreed with this notion, because some people are horrible pet owners and I wouldn't trust them on principle by them just happen to have (own) a pet. Also I may trust people who, despite wanting to have a pet, are not getting a pet since they know they may not have enough space, time or money to care for one, which also is a very responsible decision that I totally share. And even if I get a pet in the future, I wouldn't pick a pet based on my sexual preferences, but I would pick a pet which's personality would best mix and match my own, if I ever get a pet, I want it to be a companion, a friend, not a fucktoy with a pulse. Of course I would pay attention to its sexual needs and not turning a blind eye towards those and I may offer relief if needed, but I don't feel the need to force those issues. So the way I am a zoophile is way different than other zoophiles.
To me, it's more of an additional sexual orientation, one among others, but it's not a way of life or a lifestyle which seems to be the case for some other zoophiles. And don't get me wrong, I don't look down onto people who live their life (and sexuality) differently (as long as no abuse is involved, that is), which is totally fine and expected, I just wanted to make the distinction between me and most other zoophiles I met before quite clear. So, to me this was never about identity. Therefore it can't vanish over time, since I never had it, even if I tried to get into the "lifestyle" aspect of it. I wanted it to work. It just never was for me, though. So, I'm as much a zoophile as I am a bi/pan-oriented person. It's not an identity for me, just a fact of life. When I say "I am a furry", then yes, I have an identity attached to that, completely with a "fursona". But when I say "I am a zoophile", there really isn't anything different to be discovered about me than before I said it. I'd still be the same person afterwards, apart from having shared a private detail about my sexuality.
Similarly, there is no "urge" to being a zoophile that could go away, unless you consider sexuality and libido to be an "urge". I don't always fantasize about animals or look at animal junk or mating footage to get my rocks off. As this is one of many appetites for me, I like variety. What makes me hot today and totally leave my unfazed tomorrow, yet arouse me yet again the day after. Then again, this has been part of my sexuality all my life, so nothing that decreased significantly, when I got older. If anything, as with most things in life, you get used to stuff. In my youth when the Internet was really a "new thing" and pics and videos of animals doing the deed were rare to come by outside of nature shows on TV, pretty much anything I saw might have made me horny. Today I'm waaay more picky, because I've seen so much and became desensitized towards the more "usual" stuff, especially the endless torrents of dog- and horse-content which was the only true constant in all zoo communities I've seen over the years. Plus, I never was into dogs (sexually I mean) to begin with and horses and their junk (both stallions and mares) are such a common sight that they barely elicit a reaction (let alone an erection) from me. If there isn't anything rare about it, I may see it, think to myself "yet another generic looking species-x junk pic" and move on. But again, I guess this has little to do with age and much to do with just the constant exposure towards certain material. After a while it gets stale. That's normal. However I don't think that my age had any influence on my orientation and my interests (as of yet).