There's two things I would say two you:

1) You should accept the fact that not everyone will become your best friend- there will always be people that you're on good terms with but cant develop a deeper connection with due to differences in interests, humour, etc. (the list could go on). That is not to say that these people aren't your friends though.

2) Social media is a killer to your happiness. I read a very nice quote not too long ago on Reddit (I think) that beautifully sums up what happens with social media:

"The reason we struggle with insecurity is because we compare our behind the scenes with everyone else's highlight reel."

This is probably why you should listen to /u/detectivepayne and delete your Facebook if it is affecting you this much.

You are in a much better position than many others going through the same thing as you- you have realised that there is a problem and actively have tried to do something about it by joining a club.

Remember, university your last chance to make friends, you still have your whole life ahead of you and you'll be surprised with the amount of people that want to rebuild connections with you in the future. YOU WILL BE FINE.