Do you know a friend who who never picks up their cell phone, respond to ims, and never calls back? ?

It's called hibernation. I've done it for a short period of time where you dont' talk to anybody. Mind you, I told my friends that if they called or tried to contact me I wouldn't answer. It frustrated a few of my friends but the majority stood by me. It happens when you need to sort things out. It's tougher than you think. Also, he may be coming up with excuses so you don't think he's a headcase. People can be really judgemental that way.