Sucks dude. I hope the comments left for you have changed your perspective. Sometimes shit happens, and shit will happen for years if you let it. You're not what people see you as. People will see the most shallow version of you, the physical representation of it. Whatever people see is the lowest form of judgement anyone could pass onto you. They don't see the history that shaped you, they don't see what you're feeling, all they see is some loser.

Fuck all that. You're better than this slut you decided to let into your world, she may have felt good but that's what she wanted you to feel. She manipulated you to feel love. Period. And this "best friend"? He likes you because he thinks he's better than you. Why else would he fuck your girl?

Fuck all these people. You don't need friends right now, you don't need to validate your life with a girl. What you need is to spend some time alone, working on yourself.

Like I said, what people see is how they will treat you. This is awesome in many ways. What you need right now is to get your ass into shape, and start reading (If you haven't been already). Work out as much as you can, eat a lot of food, and watch the looks start changing. People are so fucking shallow they assume if you're good looking you deserve to be treated good. So why not manipulate that view into your favour? Buy nice cloths, get into shape, expand your vocabulary and you'll become the hot guy in the room. That's all it takes.

Fuck the haters, bro. You cultivated a loser life because you weren't putting in the work on yourself. You allowed these shitty people into your life, now it's time you removed them.