I have Asperger's and I will often go long stretches of time where I don't want to talk to my friends. It's not because I don't like them or don't care about them, it's just because I get mentally exhausted from socializing, and talking to people too much either becomes boring or annoying. I always need to balance socialization with alone time. There are times when I just need to get away from people - regardless of how close or not close I am to them. Although the closer I am to them, the more time I can spend with them before I have to recharge.
Needless to say, there have been quite a few people in my life who take this personally and get hurt if I do not contact them on a regular basis. When I was a little kid (elementary/primary school age) I had a friend who was obsessed with me and would follow me around and cling to me, desperately wanting me to play with her. She didn't understand the concepts of personal space and alone time, so I would deliberately start arguments with her in order to make her leave me alone.