shitty 8 years and counting

I honestly have so much on my plate I know what I should do but don’t know why I give him so many chances not to change it’s a every weekend occurrence. We have 3 children together and have been together 8 years. He just got a new job will be working nights and adds all these new people on Facebook (he’s known literally 2 days) and already trying to invite them over to drink. It makes me pissed and of course I would never allow that at my house but just makes me mad he blames everything on me. He lost his job in July for drinking one week night and missing work the next day. he talks about me to people he doesn’t know I don’t know why I give so many chances saying it’s okay.