I Feel Really Bad About This

My wife and I had two children. A boy and a girl. Our daughter befriended another girl in grade school and this girl would spend a lot of time at our house. Her mother worked a lot and her father was dead beat man whore who only came by to see her when it best suited him. She would spend weeks at time staying with us. We paid for her tuition and tutoring, clothes, food and pretty much everything else. She was, for all intents and purposes, our third child.

Now my children are all grown up. My son has his own family and my biological daughter just went off to college and my adopted daughter moved out to her own apartment and got a job at the country club here in town. My wife, sadly passed away last year after battling cancer. She was the love of my life and I fell into a deep depression. I no longer work and just spend my day gardening or working around the house. This big empty house. The only one who comes to visit me every week is my adopted daughter. She comes by once a week with food and watches TV with me in the evening. It's terrible because I saw her as my daughter but last few times she's come to see me, we end up having sex in the living room. I know she has a man who is married and much older than her who she met at the country club and I know it's not the best relationship and she drinks quite a bit. She too has been depressed and we just kind of let it happen. We don't talk about it or get romantic or anything. It just sort of happens when comes over. She'll just pull her pants down and start touching herself and I'll do the same and then we start kissing and fucking each other. I'm sure my wife is looking down at me from heaven in disappointment but I am a weak man and even though I feel terrible every time I let this happen, I also feel at peace and cared for as well.