it could be mood swings, but it doesn't sound as if your behaviour is really the problem. You seem to see what he's like clearly enough. Up to you what you do about it. You probably won't be able to change him, people can only change themselves. And the weed may be undermining his ability to do so, even if he has good intentions. It doesn't sound as though you trust him - with good reason, I expect - and that's a lousy basis for a relationship. People can change, but I wouldn't be too optimistic about this one, to be honest.