Who the @#$! cares about them?? They can do what they want. You should do you! Have your own little party! Ok babe look being lonely is hard - I know...
But in the mean time you should find things that make YOU happy. Try to find happiness in YOURSELF first and only then go and look for it in other people.

What a lot of people do when they get lonely is date random people they don't even click with, get drunk, and just walk around pretending to mix with everyone they're around even if they don't enjoy being around them. Trust me they aren't happy either and even if they are the lows beat the highs every time. That's how people get addicted to stuff btw...

Try and find things in life that just make you happy. And if you can't then you may have been spending too much time worrying about what other people like and not what you like!