Hi, I'm new on here. My husband and I separated in March after a 12 year marriage, together 14 years (one child). The family moved to Canada in May 09. We were going to try for another baby, which I really wanted. In August husband went away on a working holiday and sent me an email saying he wanted to leave, didn't want to be in Canada, told me he had cheated on me when I was heavily pregnant with our daughter (7 1/2 years before). I tried to sort things, and we reconciled for six months or so after coming back to the UK but he wouln't work, would stay on the computer all day. I asked him to leave, expecting he would realize and stop what he was doing and come back. He basically cut me off from then on (although communication had not been great before).
Anyway, I recently found out (5 weeks ago) that he has a girlfriend and they are already talking of moving in together. She has 2 little girls younger than our daughter. She is also still married and left her husband for cheating can you believe. He has confirmed the relationship is sexual and I have filed for divorce. I know in my head that I am better off without him but I can't let go. Anyway, I have emailed her and her husband and today in a moment of sheer insanity I emailed all of her work colleagues to let them know she is committing adultery and what a swine my husband is (didn't use my email account). Husband has phoned to say her place of work has reported me to the police.
I am not like this. I am rational, I am nice. What is going on!!!! I am so fed up of being in this place. I don't want him back but I want my old life. Which was far from perfect. He says he loves me but not enough. Why can't I let go, let her have him and move on. She really is getting no prince charming. My life wasn't full of roses. He was a nightmare from day one, but I did love him and put up with a lot. He never took care of us as a proper husband would and I always struggled to get him out of bed and to work.
Please if anyone has been through anything similar, I'd love to hear how you moved on. I'm loosing the plot. 
Thanks! x