DEAR AMY: Our 30-year-old son, “Thomas,” has a great job, is well-adjusted, and has many friends. Thomas is outgoing and goes out with groups of friends, some of whom are married. He is not dating anyone and hasn’t “dated” (that we know of) since high school (i.e. going to proms, dances, etc.). Thomas and I have a close relationship and talk about most any topic, except his lack of dating or of having a special someone in his life. I want to ask him why he doesn’t date, but I don’t want to put him on the spot in case that is not something he wants to talk about with his mother. My husband is n…