Could it not be that perhaps you are bisexual, have been since birth and always would have been, whether the molestation occurred or not?
And that it was in fact the molestation that rendered you unable to form emotional/sexual bonds with men?
It's important to think about things on the flip-side sometimes. You might actually be more capable of forming emotional bonds with men than you're aware of.
I form emotional bonds with men just fine... Very close and very dear friendships that have lasted decades. I still am close with the guys I hung out with in High School, 35 years later.
I am fortunate in that I did not carry away any anger or ill feeling about the experience... in fact I usually refer to it as a 'quasi'- molestation... simply because I fully recognize that i had the power to stop it at any time... and I don't even mean by 'telling' on them... I mean I simply did not have to go over there every day after school for 2 years....
I did because I was raised Catholic and had an intense curiosity in everything sexual... I kept going because it was so forbidden and so secret... and I kept going because it was intensely pleasurable...
But those were all just physical sensations and suppressed sexual curiosity.
I never kissed a guy, and never have I felt the slightest inclination to kiss a guy. While I would stare, drooling and slack jawed at a well made cock, I never turn my head to gaze at men walking down the street...
But I have all these emotional responses to women... this yarning and delight in their company, this fascination in them as persons...
So I see myself as genuinely preferring women... even though I know that sex with guys is just as, if not more pleasurable, physically... it is not as pleasurable emotionally...
That being said... I have never regretted or wished I had not had the experiences I had at that young age. It was, if nothing else, eye opening.
However... As to your point about being bisexual... I think EVERY man is born bisexual within a range of preferential leaning... one way or the other... What we call homosexual is just that 10% that overwhelmingly prefers men. And I would venture to say that only 10% overwhelming prefer women.
And the rest of us fall somewhere on the spectrum between those extremes... most of those who are 30 or 40% gay inclined choose to live heterosexual lives simply because it is easier to live that life in this culture.
I would say that I got seduced into the molestation at least in part due to that inborn flexibility of sexuality that most males have.
And, I would say that early experience tends to crystalize the final nature of that sexuality.
I would recommend the OP discuss with their guy the guy's feelings and whether they relate to something that happened in his past... or something he wishes for in his future.