As opposed to other posters, I believe his story, mostly because it sounds so far fetched. There's no way anybody in their right mind would think up that they were dealing drugs for a friend, and you'd know it was the worst thing to say to your wife, because it's so incriminating. The only thing I think he might be lying about is not having full sex with her and only a BJ. I think he's tried to minimise that.
OP. I'm so sorry, clearly he is someone who you don't even know.
I find this really appalling. No wonder you felt as you did last night. This man is actually a monster, and he can lay blame on his friend, well 1, he chose this man as a close friend, so clearly they have a lot in common. 2, he chose to sell the drugs on his own and 3, he also chose to take sex for these drugs too.
Well, I agree with the PP, he is no better than a pimp, exploiting sex from a vulnerable woman to get what he wants and feed her drug habit. It's such a sickening scenario, and the fact you have four children and he exposed them to the dangers of being a drug dealer I just can't comprehend. By doing this he's put you and your children in extreme danger, it's unbelievable really.
It's so great you have your mother who is clearly very supportive. Ignore his texts and calls. Really, he has no right to be contacting you and what he's done, he shouldn't be seeing the children either, his presence puts them in danger, he's a criminal who is inviting trouble with his actions.
Take care of yourself and the kids. That's what really matters now.