Is it me who doesn't fit in or them?

All of my friends drink to the possibly point of alcohol poisoning, do drugs, smoke their lungs out and just do really stupid stupid things. Some of my friends treat me like shit because they feel that they can. My roommates best friend spit in my face and thought it was funny, and my eyes hurt a little and I'm afraid I got something. They all want to get off my medication so they can get me drunk and laugh. I feel unimportant and belittled. Then I noticed that a lot of people do these things and I don't understand why people are SO STUPID!?!?!?! Personally, I wish the world would end or I would just be dead because I don't do any of these things because I don't want to endanger myself and make mistakes and just feel really alone, unwanted and left out. Right now I really just want to cry after the spitting incident, because the guy that spit in my face (he's friends with my roommate), she didn't say or do anything! She probably does all this crap with other people because she even says that peer pressure does it to her and she has no will power! How are people like that? I just don't understand it! Is there something wrong with me?
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I do stand up for myself, though they just laugh at me. I basically keep to myself and stay in my room. I know I won't ever do any of the things they do, I just keep to myself. I know some of them are my friends because they're actually nice to me.
Is it me who doesn't fit in or them?
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