Repeating past mistakes

Sometimes I wonder why I keep repeating these mistakes over and over again. I found out that my husband has restarted his friendship with this woman that I have asked him not to twice before. He swears he is not sleeping with her and yet I was not born yesterday either. Do I believe he is sleeping with her, my brain says no, but my heart says yes. Either way I do not wish her in my life or around anything to do with my life. I am tried of my husband's lies and broken promises, he has agree to sign divorce papers if I want them(does that me he wants to move on?) if that is what I want. I don't know what I want and yet I do. I want him gone without the hassle of it all and he won't do it that way. I mean why stay with someone if you don't want to be with them right? You would think that I am happier with my life as I try and slowly build things back the way it should be, but he is like a thorn that won't go away. I am wanting so much to better things and the devil has a way of knocking a person down but I won't let him win. My son last week got upset with another student and without thinking about his words told him that he would harm him if he didn't stop talking about him. He was suspended from school fro 10 days and I have spoken to him about his words and stopping and thinking before you speak. Life is not a straight course but one big tidal wave that takes you somewhere different each time. Does anyone care? Laura