Question about an affair and my Mother?

What do you hope to gain by confronting her? At this point, there are no parties to the affair that will be affected, especially since your father has ped away. So run the possible conversation through your head. If you confront her and she admits to it, then what? If she denies it, then what? I don't think you're really going to get anything of value out of this. If you're father was still alive, I could definately see pursuing this because there would be a victim. But now?