What's yalls opinion on divorce?

Me and my husband have been having issues and decided to give each other a little spave.. But now we are separated because of him entertaining his ex fiance behind my back, for over a month, and has even stayed two nights with her in the last week once with his daughter on the 15th and again last night cause I told him I would like him to stay somewhere else (because I need to much attention to go long periods of time with out being near him if I know he is close), thinking his camper that is sitting in the yard, instead he just leaves and when a friend of ours got a hold of him he was on his way to his exes house to stay with her.. He claims he isn't cheating but he hides the phone he texts her on from me and sneaks around to text her and this girl has no kids by him or any kind of connection besides a past sexual one.. So we get into it and He tells me he wants a divorce and that he was done with me getting mad over him being friends with his ex fiance.. he came and got his stuff from our house and brought her and her family with him and just now came back without even saying anything just walked in the house like he still lived here.. I was just wondering if anyone has any advice for me on going through a divorce because I feel like my world is falling down.. he is throwing this divorce on me on top of my mom passing away last month.. I just need some advice on what I should do..