I am now a few years older, and here is my take on it. I should have never put my mom in that position. If I am old enough to choose to make those decisions I am old enough to live in my own home where it isn't an issue.
I know the economy sucks, and you may be helping out your son by letting him live with you, but he shouldn't be allowed to play house in your house. It was tough to hear when I was that age, but now I see the importance of the lesson.
I came to know the Lord a couple of years after that, and I had a person in my family mention the things that I used to do, and it stung to hear it, but more importantly, I wasn't honoring and respecting my mom by my actions.
Hope this helps.
B
Great answer. I have also made those same points to my wife.