I feel so unqualified to offer advice. But, I know some of the pain that you describe.
I was told by my mother and her best friend during our "the birds and the bees" conversation that all women give up a piece of themselves whenever they have sex. So I needed to be certain that I wasn't a thief when I made love.
They were telling this to an 8 year old boy that had been caught repeatedly fooling around with kids in the neighborhood. The didn't know about my abuse, even though both had been victims themselves. They simply didn't do the calculus of where my behavior was coming from.
At the end of that conversation, I was convinced that my sexual desire made me a thief at best and a rapist at worst. That was a burden I didn't shed until last year, at the age of 32.
Even though I longed for female companionship, I remembered those words and my abuse and I hated myself for wanting to inflict my dirty desire on some helpless woman who would lose a piece of herself to me no matter what.
So I became unable to approach women (girls, really....I was 14 when I started trying to overcome this aversion). I believed that my presence in their life was necessarily destructive. I believed that no woman would ever want me for me and that I would have to trick them into meeting my needs.
However, I am a natural optimist. And my abuse did not kill that optimism. It just twisted and warped it. But in this case, I stumbled upon "Game Theory" which was mostly mind games to victimize the willing. But it did make me rethink my assumptions. These are the things that I needed to do to have a relationship. If any of this helps, use it. If it doesn't....keep trying. That's the hardest part.
1: If a woman is talking to you, you have a chance. If she continues talking to you after she could have politely stopped, she is enjoying herself...that's why she is still talking to you.
2: if she is enjoying herslf and you are enjoying yourself, then you have the beginning of attraction. Attraction in healthy women is very different than most men expect: attraction for the healthy woman is based upon how much you believe in your ability to attract her.
3: if you believe in yourself, then Act like it: don't apologize too much. Don't talk fast. Don't be nervous about getting your needs met. Don't focus on yourself at all. Focus on her. Get out of your own head.
4: Do not make assumptions other than this one: you will enrich her life by being in it. If that is your starting assumption, and you believe it, then she probably will too.
Ask her out. If she says yes, just focus on her. Don't expect or need anything from her. Just give her the gift of who you are. If you do, she will fall in love with you.
Having said all that, I offer this warning: you cannot feel or create chemistry if you cannot get our of your head and into the moment.