Help 😓

So I went to a concert last weekend with my boyfriend. During the concert, I got a Snapchat notification off of one of my friends who is a guy I went to school with. He asked me who it was and he asked me to open the snap in front of him to ‘ease his mind’. I did it and that was that. On the way home, we had a big argument about something he said that made me upset. He was crying and he started calling himself a mess and whatever. I told him I didn’t know if this relationship was going to work anymore and He said something along the lines of “you won’t hear from me again” or “don’t worry if you don’t hear from me again” (I cant remember exactly what he said but it was something like that). It was almost like he was saying that he was gonna kill himself. I started shouting at him, asking him if that’s what he meant and I asked “are you actually saying you’re gonna kill yourself, why would you say that? Don’t threaten me”. He never said that words “I’m going to kill myself” but I know that’s what he was trying to say. He has a bad temper and does kick off when we argue. If we are arguing in the car, he’ll punch the steering wheel and get out of the car while slamming the door. I don’t know what to do..