I don't think either side is completely on target with regard to this matter. I believe there are people who obviously choose the gay or bi lifestyle. You often here women who say they are done with men for one reason or the other. Or people like Cynthia Nixon who stated as much, but retracted her statement after the LGBT community started attacking her over the admission.
I suspect that hormones or sexual abuse play a role in sexual orientation. I don't believe scientists can prove or disprove whether or not some one is born gay. And while some would argue God wouldn't create a person as such, what would that person's argument be regarding those who are born with mental or physical defects. For the record, I'm not saying gay people are mentally or physically defective.
To the OP I would say, I'm sorry to hear about the abuse you suffered and your struggles. Try to focus more on solutions than the problems. And as some one has already suggested, think about the renewing of your mind. Allow God to transform your focus to the life he would have you live, instead of focusing on who you'd like to live it with. BTW, blaming God for your predicament will serve no good at all. No matter how you feel about yourself, God loves you.