Me and my wife have been married for 11 years and we have two boys. One is 6 and one is 4. Me and my wife never get intimate and she got fat and she let her self go. She never helps around the house and we never have sex. I have cheated on her before with one of her friends just 4 months ago. She got angry and we separated for a little bit then she stepped her games up to lose weight and be more active but she quickly got back to her old habits.

Me and my sister in law always chat online. She lives in another state and sometimes she comes visit. When she visits she stays with us and we are alone in the house sometimes. When we are alone together we talk about everything. I talk to her about my sex life and she even talks to me about her sex life with her husband. She said that sex with her husband is average and sometimes plain boring. She even said that her husband can't get it up sometimes and he often skip showers so he often smells really bad.

Me and my sister in law were enjoying chatting on Facebook and we decided that it would be a great idea to see each other. We didn't have anything that we wanted to do that we were not suppose to do. We just wanted to see each other and talk as friends. I booked early morning flight and went to see her. She picked me up at the airport and we went to her house. Her husband wasn't here. We had lunch and we chatted. And then one thing led to another and we started making out and we had sex on the couch. The sex was so great that we did it multiple times.

I was staying at a hotel and everyday while her husband was gone we would meet to go out together and have sex at the house. During the last week she told her husband that she was supposed to go on a business trip but in reality she came to my hotel room to spend a few nights with me. And then I went back to Philadelphia and from there no one knows what happened between me and her. Not her husband or my wife.

I feel guilty about it. That's why I never told my wife but the temptation to have another affair with my sister in law is still here. What should I do? Should I tell my wife or keep it a secret?