Well, I think there's two parts to your story. First, if your husband is abusive to you, get yourself and your children out of that house! If it's temporary stress, perhaps you could stay at your family's or a friend's house for a while. If it's been going on/will go on forever, get your family's help or someone from the outside, but you shouldn't have to go through that and neither should your children.
The second part then, is this guy. I think there's nothing lost by calling him up and spending some time together, even as friends. If the feelings between you will be mutual, it might be the beginnings of a wonderful relationship. On the other hand, don't run to him because you're having problems with your present husband. Also, decide what you and your husband are doing - are you going to try to work through your problems? Are you going your separate ways?
Basically, when you're clear on what you want for yourself and your children and you're in a stable situation, then go pursue this guy! That's what I think.