I can't really say much without knowing more, but just think about what would happen either way, if you did or did not choose to break your friendship. If you did, you would be breaking away from someone toxic to you, however, there is still guilt associated with that. With continuing, you risk your own happiness for theirs. My best advice is making a limit. If they are still a good friend, it is perfectly fine to be there for them and be friends, but if it gets to the point you are stressed and can't handle the bad influence, stop. That doesn't mean stop being their friend or stop caring about them, just give yourself a break from them. I have a friend similar to this who causes a lot of drama and stuff and then stresses me out, meanwhile i don't get more than a one-word answer when i am going through something. That friend and i do not talk much because they are toxic for me. But i dont know you, i dont know your friend. The best advice i know is what i have given.