I tried a few days ago to break up but it went very south very fast and to keep him from hurting himself I stayed. But when I said I thought it would be in both our best interests to split because of our current situations he said "We aren't doing this, not now not ever. I already have too much invested into us." "So no i dont care what you say, this isn't happening. I'm not letting you leave me." Then he brought his father into it (yes he had his dad text me saying why I shouldn't leave him). But the best way I can describe how he became was unhinged. I mean veins popping out and he was shaking mad. When I back tracked it was like a switch flipped and he was totally normal. I'm kind of afraid of what might happen if I do leave him.
What do I do?