Of cource it's always hard to fit in but like others said be yourself. If people don't like 당신 than find others! My 모토 is 'It's impossible until you've got someone to help you' and that also means that 당신 have to be with people who are willing to help, not just for hanging out. And if 당신 don't hang out with your 프렌즈 than either you're not up for things enough 또는 they're not your kind of people.
I'll give 당신 the 디즈니 answer and say: DON'T FIT IN, STAND OUT! Nah, I don't believe in fitting in. I believe in finding people that share common interests with you. Having 프렌즈 that 당신 can just be total dorks with and act crazy together is the real way to "fit in", mostly because that's when you're happiest.
As for why 당신 don't hang out with your friends, um idk? If 당신 want to hang out with them throw a party 또는 text one and see if they wanna go to the 영화 또는 do something.