I understand the problem you're having with your son vs your husband. I came out to my Mom when I was 14, but I didn't come out to my Dad until I was 20 and had a girlfriend (at the time). Main reason mom was easy was that I already knew she supported LGBT rights. In fact, she used to lecture me if I said anything homophobic before accepting myself. But I had no idea where my Dad stood, so I kept it from him. I'm sure my Mom told him before I did, and I wasn't mad about it since the reaction was fine. Maybe it would help to discuss with your son how you think your husband would react.