Carolyn Hax: Daughter comes out but won’t tell Dad. What now?

We have both been concerned for a while that something is bothering her, making her uncomfortable around us. Now that (I think) I know what the “something” is, I’m feeling better, though still aware that her mental health risk is higher for many reasons, including feeling the need to remain closeted. My husband is worried and perplexed, and I feel stuck in the middle — glad she shared, wanting to respect that it’s her news to share, concerned for my husband and what will happen if/when she tells him. Do I encourage her to tell him? Test him with impersonal hypotheticals? Play dumb at the revelation? Family therapy? Other?