Oh no! See if you can get counseling before you just walk away. It takes two to be in a marriage tho. My first wife wanted out too after 17 years of marriage and 2 kids, said there was nothing I could do or say. I was at work one day and a dude walks in out of the blue and serves me divorce papers. I found out she was seeing another guy while I was busting my ass at work. 23 years later, looking back on it now, it was the best thing that happened to me and I want to send her a thank you note.
I really hope the best works out for you my friend. Its a very tough spot to be in. But you will get through. We are here to support you ANYTIME.