It's not your fault. That's entirely beside the point. We at the mercy of hormones that don't deal in logic. If you disagree and tell her how lovely she is, you will be branded a liar and blind to boot. I will give you a warning.
Silence is taken as agreement.
You can't take that route either. Basically you're wrong, you're doomed, and you should die a painful death. My personal modus operandus when Mr. Icky makes his monthly house call is to have the chocolate DT's. I'm convinced my ovaries will implode if I don't have a Ben and Jerry's Chocolate Fudge Chunk. So I indulge and eye my husband for the slightest sign of disapproval.