I have an attachment issue and it's kind of ruining my life.

There are some people in my life that I have known for a long time and I love them to death, and I want to keep them around forever. However, whenever it comes to introducing new people to my life, I get really attached really quickly, and then I become super unattached just as quickly. I'm not sure if that's because of my trust issues or it's just a sort of adaptation that I've developed so I can be okay when people leave me or what, but it's driving me insane.

For the first time in a while, I was kind of forced to make friends, and I became pretty attached, and now I'm realizing I don't even really want to talk to them or anything?? I just want to be alone? And I get annoyed when any of them try to talk to me? I just want to be with my old friends. Maybe it's depression... I have no idea. Does anyone else have this?? Help!