@pinkbutterfly,
Here is my opinion. I grew up in an abusive home and I am very screwed up because of it. I don't deny that. My mother was a fool to stay in that relationship and let this man beat her and her kids. I have no respect for the woman today because of it.
That aside, I feel that you need to get out. Will your family respect you if they are attending your funeral after he kills you? Seriously, anyone who thinks you should stay in an abusive relationship does not have your best interest in mind. The concern for your well being should be more important to your family then anything else.
I am betting that he says he's sorry when you indicate that you are unhappy. He says he will stop and be a better husband, right? It's not true, and the guy is sick. Any man who hits a woman or child is not a real man, and if he hits you, he will probobly beat the children too, at some point.
I can't tell you to get a divorce, but I can tell you that I would think it very unwise to stay in an abusive marraige. Forget about the other man for now. Don't expect one man to save you from another. This is something you need to do for yourself. Right now, this other guy looks great in comparison, but don't forget that there is a reason you broke up in the first place. I'm not saying that you guys should not get back together at some point, but you first need to take care of yourself and your child.
Again, this is just my opinion.