I have a FWB I hang out with sometimes. We have known each other several years and have been on again off again through the years. Right now we have been off for about three months.

Tonight we are with friends, we are talking off to the side. She says her mom asked her today why she and I don't get married. She goes on for a few sentences. I didn't response, made a joke that fell flat, and changed the subject.

Honestly I felt like I lost frame but I'm not sure if she noticed or if it showed.

What should my response have been? Since then I've remembered a few I've said in the past but since she if FWB and I've known her for years it through me off.