I've been thinking of you. If you and your husband don't share any young children together then things should get significantly better once you finish separating your assets and he gets what he needs from your home, documents, etc.. Then you won't have to talk to him nor hear from him anymore and hopefully you'll be able to breath.
One thing I'd add from my experience is that the chance of reconciliation seems much lower the second time someone wants out of the marriage and has an affair. I don't think it matters so much how you look, whether you validate, or how frequently or infrequently you communicate at this point. It's a tragedy that it felt like your marriage was saved a few years ago and now here you are getting divorced. I'm really sorry for what you're going through. I guess a lot of stars have to align for a marriage to be successful. It still seems like the best chance for your husband to second-guess his decision will be if he and the other woman break up (and if no other woman is already standing by). There's always hope but it would be hard to trust your husband a third time if he comes back.
