Tiffy, I am glad you found us here and welcome!!

I am also bipolar 1, I also have 3 children, and I also left an extremely abusive marriage. I completely agree with roadrunner here. You understand the abusive relationship psychology which is more than alot of people do in this situation. I just want to support you in your decision to leave. I know how hard it is, and that the feelings don't just instantly dissolve.
I had fled to a women's shelter with my 5,4 and 2 and half year old. I actually had to transfer through three different shelters. I had to press charges also. So there I was with no money, no job, new town, and zero support system. It was terrifying to me. We also had no belongings except a suitcase with some clothes.
But since then I have secured us a nice home, with everything we need, put myself through collage, devolved a new support system, close ties with the community and mist of all we are happy, healthy, and for the most part have a great life. My bipolar has become more severe through the years forcing me on disability, but I know now that I can do this and I can do it alone and be happy and free. I am sharing this because I want you to know that you can do this, if I can anyone can. I never thought I could have this life, if someone told me this back then I'd total disbeleive.
My kids still suffer some bad memories of a few major events that happened and it is now 8 years later. I just couldn't take the chance of the abuse transferring from me to them. Children witnessing a parent being abused by the other parent is actually a form of abuse in itself.
I hope you can stay away from this relationship and remember that there is always a " honeymoon" stage from the abuser towards the victim. Unfortunately we all know this never lasts long before things get even worse.
If I can help you in any way, or you just want to talk, need support I'm here and I'd be happy to lend you my shoulder, ear or anything you need.