Blimey, what a horribly sad story. It may be an unpopular viewpoint, but I feel horribly sad for your boyfriend. He was a twat, yes, but how many people act in fury - and how many of them kill their friends by mistake? He has to live with this for the rest of his life and no amount of prison will be as much punishment.

I think DreamsofHome is right and he has shown honour in confessing this to you - especially early on in the relationship.  He wants to be honest and upfront and I applaud him for this. Aggression in anyone is unattractive - but if my erstwhile best friend had robbed my parents, I don't know if I'd be so restrained with my fists. It was an instant of understandable (IMO) fury and he will never be able to take back what he did. I don't think he's aggressive, either. I think walloping someone for such a huge betrayal is quite a normal human reaction - it's not right, of course not - but it doesn't make him aggressive. It makes him human!

I hope that his future is happier than his past and if you decide to be part of it I don't think that would be an unwise choice.