Married and very unhappy?

I have been married for 4 years. I've been with him a total of 8. I was 16 when we started dating, I'm now 25. I was adopted when I was 7 years old. Never really had a father figure, but believe that is part of the reason I am with my husband. After i had my daughter 3 years ago, things changed. Right after I had her he asked me "If Hannah (my daughter) and I were each in a hospital bed and you had to choose to save one of us, who would you choose?" I said my daughter, she has a full life ahead of her. He got upset with that answer. Constantly bickering back and forth. Even to the point of him SPITTING IN MY FACE. We finally seemed to be normal again. We ended up having another baby together. Now 7 months later, here we are again. He keeps throwing up the word divorce. I'm on vacation staying with my mom almost 1000 miles away, and he brings up divorce over stupid facebook stuff. I've had it. He threw it up the last time to me. What do you all think?