What is wrong? You have lost interest in everyone and everything. You always had trouble making friends; but you are drifting away from the few friends you do have. Who ever came up with the idea of friends growing apart had you in mind. It is like you are going out of your way to avoid being close to anyone.
You are only interested in things you can do by yourself; and even that is not all that interesting. If you are interested, no one can tell. You will not talk about anything, especially about what is wrong.
You are hard to understand. It seems like you have to keep anyone you are close to all to yourself. It is not exactly like being jealous. It is like their paying attention to anyone else hurts your feelings. That is not all that new. You often get your feelings hurt; but not having all of someone's attention really gets you down. When people confront you about smothering them, you get nervous and up-tight. It seems to them like you think they should feel guilty about saying anything to you.
Overwhelming people with closeness is not the end of it. Whatever they say or do, you do not say anything back. You will not stick up for yourself, no matter what. You try to please everyone and keep them happy all the time. For them, it is like having a puppy hanging on them. It is hard for them to get angry with you; but they get to where they cannot stand you. You think they do not like you. They like you but cannot handle so much of you all the time.