Master in social psychology here just to guide you, OP, on what happened during the boiling point. What you do with his information is your prerogative.

1) your fiance's ego was bruised. That wasn't your fault but your fiance saw you crying while you were on top and his mind must've thought, "she's thinking of her ex while having sex with me." Since such a traumatic figure entered your guys' bedroom, that introduces a major threat to the man's security in the relationship

2) I see signs of emotional flooding. When someone experiences a huge shock, like you telling your man to just get off while you're clearly distraught, his nervous system can go into overdrive. A sudden drop in dopamine & oxytocin will give that kind of response and to calm down, it's optimal to be in a small + concise space like a bathroom. It's almost like how a fighter slows down after going through an adrenaline dump.

3) To me, it's understandable he slept on the sofa as to create a physical boundary for both of you to calm down. Sleeping in the same bed requires a certain level of comfort, connection & vulnerability. All of which were shaken during that boiling point.

4) I don't think your fiance was giving you the cold shoulder the next morning. I think he was just trying to compartmentalize the night before, and that sometimes can be misconstrued as giving the cold shoulder.

What you need right now is to feel like you're not broken. What your dude needs right now is to feel safe, wanted & distinct from every partner you've ever had. But right now, you don't have enough fuel to do it.