Relationship advice? *EMERGANCY?

I think you need to apologise, and you need closure. Write him a letter in which you say that you regret your previous behaviour, and say that although it was to do with the loss of your friend there was no excuse for how you treated him. Say that you know it's over, but that you just needed to apologise and say how sorry you are. That way, you will be drawing a line under the relationship, and you'll feel less guilty, both of which will help you to move on.