I know my daughter’s fiancé is cheating, and she does not know I know

Dear Delyara, My daughter is getting married in three months. Last week, I saw her fiancé kissing another woman outside a restaurant. Not a friendly kiss. I sat in my car and watched long enough to remove every possible innocent explanation. He did not see me. I have told nobody. My daughter is twenty-eight, intelligent, independent, and completely in love with him. Invitations are sent. Her dress is hanging in our spare room. Yesterday, she asked whether I thought she had finally found “the safe one.” I said yes. The lie tasted physical. I keep telling myself I need more information. Perhaps they have an agreement I know nothing about. Perhaps I misunderstood something. I did not. My husband says I seem distracted. I cannot tell him because once another person knows, silence becomes a conspiracy rather than hesitation. Tonight, my daughter sent me photographs of table decorations. I stared at the screen thinking, If I tell you, I may destroy the wedding. If I do not tell you, I may help destroy the marriage. Motherhood used to mean knowing how to protect her. Now every option feels like choosing which kind of pain to hand my own child.