When ppl tells u are pretty but u dont feel like that.

My friends always say that I am pretty, but I dont feel pretty at all. Like, why nobody approaches to me? Is it because im too weird? Too fat? Too ugly? When I have a crush on someone I feel like a predator, and it never ends up well. Like I am literally convinced that I am the ugliest person in the world, ppl has been always bullied me since I was in kindergarten because of the way I look and for the way I am. I dont know whats wrong with me… I learned that ppl dont care about of how weird u are as long as youre pretty, and it hurts me so much. I dont know what to do… T_T