For me, the egg came before the chicken.
I was gay before the abuse, during the abuse and after. This question was simply never an issue in my case.
Except, of course, for the 23 year detour through a marriage, fathering three children, and a full length active duty military career.
In your case, TofT, it would seem that issues of self esteem, self body image, and/or self worth are also mixed up with your questions about sexual orientation. Unravelling all that could take some time (quite a bit) and might be easier if you somehow could obtain the help of a therapist. I know that's not always practical or feasible but check out your local resources, some of which might be low cost or no cost public facilities.
I think that I am starting to ramble here, so will sign off with best wishes.
Be gentle and patient with yourself.
"We are only two and yet our howling can encircle the world's end.
Frightened, you are my only friend.
And frightened we are, every one.
Someone must take a stand -- Coward, take my coward's hand"