Trisk

Okay I'm not sure if this belongs in this forum exactly because it's not about sexuality...but this does seem to be the place people go for relationship advice...but this is more about a friendship.
So here it goes.

It's kind of strange. I live in an apartment building. And I'm friends with this guy who is about 10 years older than me, who I met in the building through a mutual friend. I always liked talking to him because he seemed smart and had maturity beyond what a lot of people my own age seem to have...which I like, because it makes for good, interesting conversation.

I've been friends with him for a few years and at first it was just cool. We hung out and talked. But over time, it became clear that he had some issues. He didn't have a lot of friends, he had issues with friends in the past(i think during a crisis, a lot of his "friends" sort of abandoned him), he had issues with girls(bad breakup), he was mildly OCD about cleanliness (but not enough for real treatment) and he had anxiety issues (really bad anxiety attacks occasionally).
Now...in case you can't see how this would be a bad mixture....the OCD leads to anxiety. The issues he has lead to anxiety. Anxiety needs dealing with. Without many friends, he only has a few people to go to about these problems. So I was usually either the person he would go to about these problems or the person he would take out all his anxiety on. And it was horrible. It got to the point where we were fighting nonstop. Pretty much every other day, we were fighting about something or another because he was always anxious and I wasnt always there for him. I wanted to go out with my friends and have fun and he wanted me to sit in the building and listen to him whine. It got to the point where he'd start calling me when I was with my friends and scream at me for being with them two days in a row (Friday night and Saturday). He would constantly insult me...saying that the only reason anyone would do that is because they were insecure and trying to hard (wtf?)...and tell me I was a horrible friend and all this crap.
Later on, he would sometimes say he was sorry and he was being unreasonable but he'd always get anxious again and it would start up.

Eventually, I couldnt take it anymore. I'm young and I need to enjoy my life. I can't constantly be looking after the problems of someone who's 10 years older than me. He needs to start to figure things out for himself. Right?
It was so hard to break it off with him. He kept coming to my house...crying. Yes, crying. A grown man. And I would just tell him to stop and close the door. It was hard and I felt bad but it was really psychotic. I actually started to have nightmares about being stalked by him.

So...6 months later...with the urging of my friend, I decided to let him back into my life. Apparently he had been through a lot of therapy and stuff...so I figured I'd give him another chance. I felt so guilty about the way I had so bluntly ended our friendship. So I started talking to him again and all this crap...and he was A LOT better for a long time. Apparently the therapy made a huge amount of difference. So we were cool for a while.
But very gradually, I noticed certain things coming back. And now...after almost a year...things are almost the way they were before I broke off our friendship. He gets mad at me if I'm busy for two days and don't try to contact him. He yells at me about what kind of friend I "should be". I went on vacation for four days or so a few weeks ago and he said he missed me. WTF?

So yesterday, I had a class until 4:30. He had called me earlier that day and yelled at me and then sent me an angry message in class (on my cell). Some time later, I got another message from him saying "I'm in a bad mood." So the class ended at 4:30 and I went back to my place and I lost track of time and by 7, I still hadn't contacted him. So he called me and started screaming, saying I should have contacted him earlier because any good friend would be concerned when their friend was in a bad mood. He then informed me that he didn't want to talk anymore and hung up. 5 minutes later, he went online and yelled at me some more, signing off before I could respond. I tried to call him back but he didnt pick up, so I figured he had gone to someone else for help. I saw him in the building at 8:00 but he still didn't want to talk to me so I shrugged and went on my way. At 9:30, he called me up screaming again, saying I should have tried harder to contact him and talk to him before, and now I should go to his house. I informed him that I was with a friend and that pissed him off too. The fight is continuing today. I really don't know how to deal with him anymore.

I need some help. WHat would you do? I'm moving in a month so I'm thinking that maybe I should just apologize and end on good terms with him so I don't screw him up even more. But on the other hand...there is so much shit I want to say to him. He is so aggrivating and I'm not so sure I'm being unreasonable. The problem is...he has so many issues that if I even said half the things I was thinking, I'd never see the end of it and neither would he, in terms of therapyl. DO you think I'm being unreasonable? I think it's so rediculous that he's always telling me what I "should have done, as a good friend". Who does this? The only time when you have an obligation to do certain things for people is when you're going out....at least that's what I thought. Is my thinking flawed?
I need some objective perspective on this. A lot of my friends don't like him because of all the stress he has caused me in the past. And they think it's weird that I hang out with someone older than me. Some of them even think he might be in love with me. I always tell them that's rediculous but I don't see any other reason why he'd be so attatched and needy all the time. What do you think?

Sorry this is so long.