I'm not sure if this is the right board to post but hoping this would be the place to shed some light/help with what my best friend and I have gone through. I'm baffled, hurt and angry at how things have gone down and just don't know and can't understand why he has acted like he did. But here's the bones of it below:
So, the background is that we have been best friends for the last 15 years or so and about 5 years ago we started a business together. It was my idea and I asked him if he would be interested in doing it. He was, and was more than vocal about the possibilities and branching out and whatnot. As we were working on the first project together it became increasingly clear that the bulk of the workload was falling on me; I was getting by on 3 or 4 hours of sleep a night trying to make it work, he was sitting at home watching movies every night. I had hinted and tried to bring it up a few times, trying to correct the balance of work, but every time he just ignored me. Many times he wouldn't turn up for a day here and there, on occasion he was a no show for 2, 3, 4 or 5 weeks. At one point I hadn't heard from him in 3 months! Finally, in the summer when the workload got too much for me to handle both physically and mentally, I sent him an email telling him that I was stretched to the bone and that if we were to continue the balance would need to be evened out as I couldn't continue the way it was going. There was nothing provocative in the email and it was all put nicely. I even ended it saying that it would be gutting if he decided he didn't want to be involved any more, but that "$#%^ happens" and there would be no hard feelings and we could continue hanging out and doing the other stuff we would have done outside this business aspect. I should also point out that financially, I contributed 99% of all money that went into the business/project, with him usually saying he didn't have the money to contribute. But I never once complained or mentioned that side of things to him, either in person or in my emails.
Anyway, his reply to my email was just short of character assassination. According to him the business side was "never collaborative" as I wouldn't ever listen to anyone else's input (this was provably false!), he said he didn't agree with many of the decisions made on the project (despite never once voicing any concerns and freely contributing to the plan we laid out), he was most of the time just "blowing smoke up [my] a*se for an easy life", he apparently was only ever in it to "help a friend work on a project and nothing more" (despite coming on board to jointly set up the company and right from the word go coming up with other angles we could approach and other ideas we could work on). He also highlighted the extensive input that someone involved offered, including so much of their time, praising this person beyond belief for their help, and then accused me of wanting to sack them on a number of occasions (this was completely and utterly false!). Winding up he said that he had absolutely "no interest whatsoever... none!" in doing any of the recreational stuff we had planned and was again just "blowing smoke". He painted this picture of himself as being this "easygoing dude" who is just out for an easy life with no confrontation (I've known him 15-20 years and know this *not* to be the case) and that he should have said something sooner but was just keeping the peace type thing. His last line was, "So, as far as the company goes, wind it up any time you want as my involvement is done and dusted!"
I replied to this email - again made sure it was *not* confrontational, told him that I was gutted he felt that way about everything, but likewise called him out on every point that he mentioned that I new to be false or embellished. A couple of weeks went by and then he called me up, and the first thing he said was "I'm going to give this thing a go" and said he was on board and that it was just getting on top of him that most of the time I was getting in touch in recent months it was about this project we were working on. I explained my position and he explained his. I told him I was glad we had it sorted out and reiterated that any time he wasn't into doing it he could just say and there would never be any hard feelings. We left it where he said, "Right, I'll give you a shout next week and then we'll start rattling this thing out" and again he went into the "we could also do this and that" bit about projects for after this one. I never heard from him that next week. This was 3 months ago. The other day a mutual friend was looking for a book that he loaned me to be returned. My friend/business partner had it in his house, so I texted him with the standard 'in-joke' greeting that we have also done in texts and asked if he could leave the book up to my house or I could call down for it. He replied simply, "I'll leave it up sometime this week." This morning I was in the hallway at home and heard a rattle at the door. I thought it was the postman but when I turned around saw my 'friend' turning to walk away through the frosted glass. The book was on the doormat. So, knowing I was in there was no knock or whatever, just the book in the door and he was gone.
I am truly baffled. Hurt, mainly, but also angry. In my mind I have done nothing to merit these sorts of responses from him, other than asking him - politely and constructively - to do his fair share of the stuff that we were working at. I came on here because maybe people can shed some light on if it might be me that's the problem in some way even though I cannot see how it could be. I believe that maybe his response is some sort of angry reflex on the defensive, somehow blaming me for his lack of interest or input, and maybe his is embarrassed (inwardly) at his lack of contribution over the last number of years - gone too far now to turn back time and actually do his fair share of the work. Could this be the case? Or does he just hate me for some reason? Is he angry at me for questioning his work input? Believe me, if you knew the extent of it, I was well within my rights to go mad about his lack of input, but I really, truly, kept it completely friendly and constructive at all times. He just seems to have completely turned on me. I'm almost sick inside wondering about it.

Thanks so much for taking the time to read this *very* long post.
Have a great evening everyone,
A