you dont have to choose between EITHER rising to his bait and fighting him on something OR just keeping quiet.
You also have the choice of making a small, hopefully gentle statement along the lines of, "I'm happy with the way I am in that area", and/or "it makes me feel bad when you talk to me like that", and let it finish there.
My current status: june 2006. Wife ran out and filed D. Finalized Jan 11, 2010, after 12.5 years M. 3 wonderful sons caught in the middle