I wrote a description of one of a friend of mine's adventures here: http://bullyfucksmymom.com/real-life-discussions/milf-mom-and-her-young-lover/

Her situation was not unlike yours, and she took some of the same decisions, like fucking her son's class-mate, and flirt with him in front of her son. I don't know if you are a good mother, but I think you are a good and sensual woman. You are doing as good as you can anyway, and one can't really demand more than that.