Aita for being upset

My husband and I got into a huge fight because he accused me of cheating on him with his brother. I have never cheated nor given any indication that I like his brother. I actually think he's a sleazy scumbag but irrelevant. He was so paranoid that he said he was going TO DIVORCE ME OVER IT. I flipped out and was like what the fuck you don't even have a valid reason for thinking it? He couldnt give me a reason and then went and slept in the living room. The next day he comes up to me and tells me that he scheduled my "mommy makeover" plastic surgery consultation. He eventually apologized for "acting crazy" but followed it with "if i ever ACTUALLY find out you've cheated on me I will murder you and the person you did it with. I will be in prison so our kids will live with your parents." I seriously don't know if I can give much grace here. I know he has extreme paranoia issues but I don't know if i can handle being talked to like this anymore.