Abuse?

I think my boyfriend is abusive or verging on abusive. We have a daughter together but he’s not stable and I’m not sure if I should stay or not. He threatens suicide multiple times a week, told me he would stab himself in front of me and his kids. Yells at me over anything and everything, takes his anger out on me, Doesn’t Help with our daughter or does the least he can including financially, he’ll grab me sometimes during fights or prevent me from leaving and he tries to control my phone usage and social media by guilting me. Drugs and cigarettes come before his kids needs. He also can’t hold a job. Hasn’t held one for more than since 3 months in the almost year and a half we’ve been together. He’ll also call me names, selfish and idiot are his favorites, and let’s his family treat me horribly. The most alarming though was that on two separate occasions he pulled out a knife during a fight and once stabbed the bed I was sitting on and second stabbed a notebook in the car while we were driving and proceeded to scream at me. He’s also straight out said he’s wanted to hit me along with accusing me of cheating and lying daily.

I can’t bring myself to leave as I do love him and hope he changes like he says he will and because I’m scared. He talks in detail on how he’ll kill the mother of his son.