Now, I never really had this problem all that much, because I never really became attached to any of my "friends", so I never cared to stop talking with them, but one thing I can say is, worry about the one you care for the most.
Although you can have friends that are understanding of what's going on with other people, sometimes you don't. Sometimes you have people who want you to make a choice between them and someone else, and my advise is to never choose the person that is trying to control your life for you. Do what you want to do, what will make you happy, not what will make someone else happy. I ended up in a situation where I had to choose between the people I hung out with, or my girlfriend.
And you know what?
Now I'm married, and I'm happy. I don't have selfish jerks trying to control my life because I entertain them. I'm with someone who actually cares and understands me, which is worth more to me than all of the friends in the world. I know that most people need more than one person in their life, they need to be social. But I'm happy. I'm happier than I ever thought I would be, because I made my choice.
Honestly, I don't want friends. Me and my wife have tried to have friends, and we just don't like it. We're a pair of anti-social introverts, and that's the way we like it. But good luck to all of you guys, whether you want to have friends, or relationships, or both, or neither.
You all deserve what you want, and don't let other people try to take that away from you, because there are people out there who will try.
Sorry if this seemed a little weird or crazy or whatever, it's just something I wanted to put out there.