My husband was changing and I didn't know why

I am the kind of person who wants to believe the best out of everyone. He started being "ugly" towards me, calling me names, calling all of my friends names... such as with one really good friend of mine that came over alot, he would call her "fatty" and then if that wasn't bad enough, he started being "ugly" to my kids. By this time, I had my oldest daughter out of the house, and had my middle daughter(a teen at the time), my youngest son, and OUR daughter. He started throwing fits over things that they did, always on my case about everything they did and if that wasn't enough, he one day threw a loaf of bread at my teen and started laughing at her. I don't know what was going on in his mind but actually she ended up throwing the loaf of bread back at him because he had been acting like a stinker for awhile and we were all tired of it. He started demanding that I buy certain products at the grocery store, wanted to have certain things to eat, and MY cooking wasn't good enough for him all of a sudden. Things changed so quickly and I just didn't know why. Jobs would call for him and he told me to tell them he would be there at a certain time, but instead, he would not show up. You know, I just thought that maybe he was going through a hard time, losing his boss, who was like a father to him.. maybe the stress of new jobs, getting a new business of his own started but I thought maybe things would get better. I wanted to believe the best in him and I stuck through alot of things he did to me that hurt so much. What else could I do ?