I've a feeling I may take some crap for this, but... here goes.
I understand to some degree what it feels like to have something that is inherent to who you are, something you can't change, be held against you. Whether it's sexuality or sexual identity or race or handicap (or whatever), it's deeply hurtful to be pre-judged by people who know one thing about you, barely know that, and yet feel that because of that they know you and can condemn you.
And yet, well... My experience is informed by this. I knew a young woman in college I'll call "M". And her thing was that she might as well have introduced herself as "Hi I'm bisexual. My name is 'M'." Being bisexual was almost literally the first thing she wanted everyone to know, and how hard it was to be bisexual, and how judgemental everyone was about her being bisexual, and... Well, you get the point.
A lot of people I knew in college were going through one form or another of coming to terms with themselves, sexually or otherwise. (Including myself.) A couple of close friends and a couple of girlfriends were openly bisexual, but they were both a lot quieter about it, and as far as I could tell, a lot happier about the fact as well.
"M" wasn't happy about it. She was unhealthy about her fixation with being bisexual, and she was incredibly tedious to be around a lot of the time as a result. She grew up in a setting where her bisexuality was undoubtedly more controversial and painful, and simply couldn't get it that she was now in a setting where that controversy was hardly a factor.
I guess what I want to say is that our sexuality will unquestionably inform on who we are, and I'm glad the author's experiences allowed him to understand an aspect of himself more fully. But I don't think it's ever "healthy" to make something like one's sexuality the central aspect of who you are. It may be hard to overcome the desire to "push back" if you feel something important to you has long been repressed; it's possible such a reaction is all but inevitable. But it seems to me that many people develop less as people for making such a reaction a central tenet of their lives.
I'm a lot of things, good, bad, and indifferent, some more fully realized than others, some that I'm still coming to terms with, some that I'm working to overcome. My sexuality is only one of them.