Dangerous situation.

Me and my boyfriend live together. It’s been very rocky to say the least. I’ve always forgiven him. I’ve looked past it. But now I’m actually scared. He drinks every night and every night we fight and almost every time he tries to leave and drive drunk (I hide his keys now) or he wants to commit suicide. I’m scared of him. Scared of what he might do to himself and scared of what he might do to me. Despite restless nights never ending fights and sometimes being scared for my own life I love him very much. I care for him and I’m scared to leave. I’m scared to be without him. I’m scared of what he might do without me. I’ve thought about contacting his family about getting him some help wether that be rehab or a mental institution. I don’t know if that’s the right thing to do though... I’m not close to them at all. I’ve only met them a handful of times because they live pretty far away. I can’t keep it up though ... I’m honestly at my whits end... should I contact his family? Should I leave? Should I stay and help him?