Suicidal husband?

My husband and I haven’t had the best last year and every time we get into a fight he always says how selfish he is and how the world would be so much better without him. All he does is hurt people around and can never do anything right. He says he should just die. I hate hearing these words from him and it breaks my heart. Idk what to do. I’ve been considering about taking time apart not because of the suicidal statements but because I’m not happy but I’m scared to leave him. He says when I leave him he will end his life.