Grown-up sleepovers: Kate Holmquist Irish Times. Terence Herron FTAI, responds to the question

Grown-up ‘sleepovers’
Tell Me About It – Kate Holmquist answers your questions
Tue, Mar 26, 2013, 00:00 – Irish Times

Q I went up to my son’s bedroom one morning to see two heads in the bed, one a stranger’s. In the past, I have allowed my young-adult children to have girlfriends/boyfriends sleep over, but as it happens these have always been long-term relationships. This new girl, my son says, is “just a friend”.
I am worried that she is going to be hurt because I know he is not interested in commitment at this time. I don’t know how to talk to him about this and can hardly ban sleepovers now that a precedent has been set.
A I can imagine your surprise as well as your attempts to remain the liberal mother in this awkward situation, but you can hardly be expected to remain serenely oblivious when passing a stranger on the way to the bathroom. Will your son start bringing one-night stands home on a regular basis? Is his claim that they’re “just friends” credible?
After reading your letter, Terence Herron, family and couples therapist with the Family Therapy Association of Ireland, comments: “The writer feels major concern for a person she doesn’t know, more so than for her own needs and her own home. She should check out her own needs first.”
He suggests that the real issue isn’t the young woman’s feelings, but your own need to tell your son: “I’m not happy with you bringing home strange girls. I was happy with sleepovers in the past because you were in a long-term boyfriend/girlfriend relationship where we knew the young woman, but I’m not happy with this.”
It’s not a moral issue. You are entitled to your space.
“What I am hearing a lot these days is that in some cases it’s very hard for the parents of adult children living at home to assert themselves,” says Herron. Don’t let your son push your guilt buttons.He may accuse you of being too strict, but being liberal doesn’t mean anything goes in your house.