I see Mr. Cordero has undertaken to answer your good question, James.
First let me thank you for your kind comments. Your question is a difficult one to answer, but not one that is without answer.
If a homosexual, or anyone else who questions their own practices or behavior, determines the way he or she is living is not good, meaning, it is in some way self-destructive and inimical to their own long-term happiness and enjoyment of life, the only thing that must be done to correct that behavior is to determinedly choose to make that change and to be willing to pay the price. There is always a price.
The price is also a result of our nature. The longer one practices anything, espeically if that thing involves pleasure and is a part of many different aspects of ones life, the more all of one's thinking and behaving related to it is habitulaized. Because habitualization is such a powerful and necessary aspect of a rational consciousness, the stronger that habitualization, the more painful and difficult it is to reprogram it and habitualize a more benevolent set of behaviors.
That is the answer to the easy part of your question. The hard part is "the approach a homosexual should take to examine," his life. I take your question at face value, and assume the homosexual wants to examine his life. You apparently have, because you say, "I have thought long and hard about what makes me homosexual."
The very first difficulty is what you and I mean by "homosexual." When I say homosexual, I mean the practice of homosexuality, but your statement, "I have thought long and hard about what makes me homosexual," is a tacit assumption it is something you are, not something you do. But, in fact, everything we do is for some reason, and the motivation for all action is desire, even when the object of desire is very remote. If we desire nothing, we do nothing.
There is another aspect of this question that makes it particularly hard for me, because I have no idea, experientially, why one would choose to be a homosexual (I mean the behavior). I must assume, the homosexual means, when he says, "why am I a homosexual," it is not his behavior he means [because the answer to that is he chose to], but, "why do I have desires or feelings which make me want to behave as a homosexual?"
The reason I think it is paramount to distinguish between homosexual desires and homosexual behavior is because lumping them together and treating them as though they are an individual's identity ignores the most important aspect of all human behavior, it is all chosen--that is what makes us volitional moral beings.
In that light, when you asked yourself the question, "what makes me homosexual?" there are two different things being asked, "what makes me choose to behave as a homosexual?" to which the answer must be, you have a desire to and you choose to fulfill that desire; but the other question is, "what makes me have those desires?"
It is the second question that today is answered by homosexuals and psychologists, "well, one is just born with the desires they have." But we aren't born with any specific desires, only generalized ones. We are born with the desire for food (hunger) but have no idea what food is, or what kind we'll like, or which is good for us or which is bad. The general desire for food does not tell us, we must use our minds to discover it, and only after we learn those things do we develop desires for specific foods, for example.
Sexual desire is no different. The ability to experience pleasure from stimulation of the genitals exists, possibly from birth, but at least from those ages when the first learning is taking place. Part of habitualization (I know technically there is no such word) is association. Part of how we develop our sexual desires (like the way we develop our gastronomic desires) is by association. We associate those things that accompany pleasure with the pleasure itself. One very important aspect of sexual pleasure and desire is that merely thinking about it produces both some pleasure and some desire.
We are not born with any specific sexual desire (i.e. for any specific object or action to fulfill it) but develop those specific desires through our associations, experiences, and thinking. I do not know why homosexuals develop the desires they do specifically, because obviously my associations, experiences, and thoughts were not those that lead to those kinds of desires. I suspect I was subjected to many of the same kinds of experiences that could have lead to homosexuality, if I had thought about them differently, but that is only conjecture on my part. Those homosexuals I know personally who have taken the time to explain some of their own experiences all came to their homosexuality along different routes and from different experiences, but all of them at some point made a conscious choice, almost a defiant one, to pursue sexual pleasure in that way.
Can a homosexual change? Honestly, James, I doubt very much someone who has been a homosexual for very long will change, because they are probably never going to reach that place in their life where they want to. Even if that should happen (and it has) the reinforcement of those particular habitualized behaviors is so strong, and changing them so difficult and painful, I must honestly say, I think there is little possibility of change, except under some extraordinary circumstances.
Does that let those homosexuals who have decided it is not an appropriate practice "off the hook" morally, I mean, if they cannot change. Yes, I think it does in this sense. We are morally responsible only for what we know and what we can do. I think it would be wrong for the homosexual to attempt to pass-off his behavior as, "normal," but it is not immoral. And, of course, the homosexual must take all the ordinary precautions in sex to insure no one, including himself, is harmed.
I doubt that this answer is adequate. There are so many questions it obviously does not answer. I believe homosexuality is ultimately a result of the choices one makes, and I think those choice are mistaken. I think all mistaken choices have bad consequences. In the case of homosexuality, only the one making those choices suffers those consequences, and however wrong they are, it is nobody else's business, not even mine. But you asked.