It is really hard for me to stay in touch with people. A lot has to do with my mental illness, but it becomes a chore for me to stay in touch with my friends from college. They call me, invite me places, but depending on my mood, I ignore them for the most part. Every now and then we have a good conversation. But they never give up on inviting me to things and I find solace in that. That they haven't given up on me. It is just so hard to maintain friendships for me. Maybe your friends feel the same way, that it's hard to keep up with people you don't see everyday. Maybe they are very busy or under a lot of stress. If they mean something to you, I wouldnt give up on them.