Love is no excuse to stay with a "man" that puts his hands on you. I would rather have my kids be in a broken family than have my son grow up and think its okay to put his hands on a woman or my daughter thinking it's okay to be beat on. You need to do what's right for you and your family and what's right is for you is to leave before you or your kids end up in the hospital or worse.
My mom went through the same thing with my father when I was a baby and even while she was pregnant with me and I'm not going to go into details but the something happened and I was taken by the police from my mom and the only way she could get me back is if she left. I don't know how long it would've taken my mom to leave if that didn't happen but to think that I could have grown up seeing my dad hitting my mother would have messed me up more then me having to deal with my parents divorce.
Now I do believe that people like your husband can change but risking to see if he will is not worth your safety especially when your kids are involved.
Take my hand I give it to you now you own me all I am. You said you would never leave me I believe you, I believe.