I don't know if I can handle a relationship

I've never really dated.
In the past when I have dated, it was maybe one date that directly led to a relationship that I've had to struggle to get out of, the last one being a year long (the one before that lasted a month, I've only ever had 2 relationships). For some reason they get super clingy really fast, and being someone who like alone time and am rather independent, I hate it. It's easy for me to make guy friends but as soon as I'm interacting with a guy I know is interested in me I feel extremely uncomfortable and want to drive him away. I recently joined a dating site hoping to ease some of my uncomfortableness in a dating situation but I think it's just gotten worse.

I know it's me that's the problem, when I see a guy that's interested in me I can only think about how he doesn't give a crap about me and just wants to get me into bed. I think about them putting their grimy hands on me or shoving their slimy tongue into my mouth and it makes me sick. Even the thought about them putting their arm around me or staring at my chest makes me disgusted. When they give me compliments I freeze up and get angry (not out loud though, it's more like a rush of angry feeling) and I don't respond. Sometimes my reactions to seemingly simple or innocent things is so negative it surprises even me.

For the most part the guys I date are nice and considerate (I've had a few bad experiences) but I still feel the same way. I think it's that I'm too afraid things will move to fast and I'll get roped into a relationship again that I don't want and am unable to escape from, or that I feel too much is expected from me, or that all they want is to see me naked.

I don't know what to do, it seems like it would be easier to abstain from relationships and dating and sex than it would be to go through these motions again or trying to date. I even considered that it meant I wasn't interested in guys anymore, but even thinking of another girl feeling me up or putting their tongue in my mouth makes me sick, so it's not that I've turned lesbian. Maybe I've gone asexual.

What's wrong with me?