TLDR: Title

I would say I have a healthy amount of confidence, know where my strengths and weaknesses are and can laugh about myself. Over the last few years I finally realized that I'm actually fairly good looking, too although I always thought of myself as ugly before.

Sounds good, right? Well all of that goes out the window when it comes to dating. When I'm out and I see a cute girl I'd like to get to know I don't think "Hey, she's cute. I should talk to her!", I think "Hey, she's cute. I'm way too skinny for her. She probably thinks my tattoo is dumb. I didn't have a haircut in 3 weeks and probably look like a hobo. There's no way she'd be interested"

The stupidest part about it is that I also have this thought process if I receive positive feedback. A few weeks ago I was at a party and this really cute girl smiled at me and obviously tried to close the gap while dancing. I smiled back and did NOTHING. I just stood there thinking "She probably didn't mean to smile at me. I'm sure she just wants to dance and not be bothered. I should just leave her alone". Afterwards my friend told me "Dude, there were 2 really good looking women obviously interested in you and you just look away! Why would you do that?" I didn't have an answer to that. I didn't even consider the possibility that they actually WANTED to get to know me. During these situations, the best case scenario I can imagine is them tolerating me which - of course - is bullshit if they actively seek eye contact and smile at me.

When in a relationship, I'm also a little bit like this (although not to the same extent). Meaning I always or often view things as favors towards me when in fact it is just a mutual interest.

So yeah, any advice for some dude who constantly keeps cockblocking himself?