First of all, your relationship is done. Whether you want to believe it or not, I [38m] would be a million dollars that if you try to limp on with this relationship, it's going to get worse and worse until someone actually gets hurt. Not like child-type "owww my feelings are hurt", but actually hurt physically and mentally. The repeated calling you after you hang up is a serious red flag.. it means you're driving him nuts, but he doesn't want to let go of you. That's a dangerous situation, especially if you honestly don't understand why he's so upset.

I'm not going to tell Jared to fuck off

Then I'm with your boyfriend in this respect.. you're either playing with Fred's feelings like he's a toy, or Jared has some info on you that you don't want Fred to know about. Unless you can explain why it's a "patently bad idea" to tell this guy not to contact you, I don't get it.

But really, the main point is.. all the hyperventillating and the fighting is not worth it, and it could end up hurting you or him permanently if you don't start prioritizing general safety and well-being over "happiness".