repulsion towards sex since childhood + PTSD symptoms

Okay. I have no idea how to seek help for this or what is going on. I don't know exactly what I'm looking for- not a diagnosis, obviously. Maybe just some kind of validation. This is a bit long.

I have a severe, almost obsessive repulsion towards sex. I'm a 22 year old female and I was in a sexually abusive relationship when I was 17 but this has been going on long LONG before that and in fact I think this problem aggravated the abuse in ways. My mother has memories of me panicking about sex when I was about nine. I identify as a lesbian and I honestly don't like the idea of sex with women either, but I'm absolutely horrified by the idea of male genitalia or men coming near me in a sexual or romantic manner (even if they're being polite and just flirting I panic because that's the association I make without meaning to). I don't know exactly why.

I've been told by a few professionals that I have PTSD symptoms but I don't think it makes sense because they've existed before the abusive relationship and didn't change much after. My mom has asked me if anything happening to me as a kid, because this started out of nowhere when I was pre-pubescent, but I really don't remember anything. I have been diagnosed with a dissociative disorder and in general this effects my memory badly, and I have almost no memories of my life prior to when I was probably nine, so I have no idea. But I know that repressed memories are a very controversial topic in psychology that a lot of researchers don't even like to entertain so that alone is enough to make me doubt that anything has happened.

I do have symptoms that coincide with childhood abuse victims', though. I acted inappropriate sexually when I was around eleven but I was still disgusted by sex and went through a very long period where I wouldn't let men, even my father, touch me innocuously, like on the back or shoulder. It still makes me feel panicky and sick but I try to tolerate it. I often dissociate in relation to sexual topics- ie, if a movie is sexual, especially if it's violent, or if a conversation becomes sexual in a detailed manner, or anything like this, I can end up losing an hour through dissociation and come back feeling sick.

This is actually becoming a huge problem in my life. It's not like I don't think about sex, I do, I'm a twenty two year old, but it causes horrible feelings. Sometimes the thoughts about sex are intrusive and violent and that's when it's the worst, when I can't control them and they end up making me dissociate. This happened even today, where I was at the coffee shop, started having intrusive unsettling sexual thoughts, and dissociated right there.

If someone has a similar experience, or an idea of where to look for help (like what kind of specialist) or any kind of coping mechanism, that would be great. Just talking to me about this would probably be a relief. Also I have no idea how valid the principle of repressed memories are so if that's something you know about I'd like to hear that too.