I am 23.
I was never the pretty one at school but have come into myself a bit over the past couple of years. When I'm in good shape, wearing makeup, flattering clothes, I can pass as attractive, even pretty (in the right light, mind!)
Over the years a few (desperate) men have I guess pursued me but i have not been interested them in a romantic way, more as friends.
I online date and have had a fair few dates out of that. The majority of which I clicked with but not romantically, although a couple didn't want to take things further with me.
Anyway long story short I'm average to below average physically. The people I like never like me back!
I have sought validation from men over the years by internalising how they treat me, and equating this to attractive I must be. As you can imagine this is pretty demoralising.
I recently went on a date with someone who was very physically attractive (out of my league!) but quite shy. He said he liked me a lot but I am not sure whether that was just because he is keen on having a girlfriend. He doesn't have much success with women. Even though I'm not sure whether I fancy him, I am obsessed with wanting him to like me - any perceived rejection is actually making me want him more 
This sounds terrible but I can't trust him or be myself because I worry that I'll disgust him. I worry that that's why he's cooling off now actually - not because he's busy over the Xmas period but because he finds me ugly.
It's tearing me apart.
It's really holding me back from getting to know someone properly, I feel like fucking princess Fiona from shrek. In flattering clothing, in a darkish room with makeup on, I look great but see me the next day and I'm fucking hideous 
Someone help. I'm having therapy at the moment for other things and don't trust myself to bring this up. I just want to die.