Honey, I went thru EXACTLY this same thing about 3 1/2 years ago with my spouse of 29 years. Our marriage was much the same as what you have posted about yours. Basically dead, but in it for the kids. He was very cool twards me, there was no affection, much less sex. We where more like roomates with children. I found out by accident that he was cheating. I felt so used and stupid. How did I not know? It is a very common to feel this way. Don't beat yourself up, please. I ended our marriage, some things just can't be rebuilt. I was crushed beyond belief. It was hard, I was hurt, sad and angry, but it got better in time. The kids took it very well, much better then I expected. Kids are a lot smarter about the atmosphere in a home then we give them credit. I can look back and say it was the best thing that happened to me. I have a new life, and am happy for the first time in years. My children are happy. also. I am not suggesting this is the answer. Every situation is different. but not to long ago, I was in your position. I know the pain and the fear you are feeling right now. If you want to PM me, please do. I wish I could give you a hug, sweetie.I want the best for you.