What is the worst thing you can say to a lady?

1620, painting by Marcus Gheeraerts

I think up there on the list of what is the worst thing you can say, is when someone asks me, "when are you expecting?" I wonder if the regret and angst of the foolish questioner lasts even a fraction of the time that the shame and hurt belonging to the questioned one lasts.
Today the nicest lady asked me that when I was wearing a huge coat and scarf! It was 19 degrees outside and I felt more like an astronaut, with all my layers on, than a young pregnant maiden. I hurriedly reassured her that I was way, way too old to be pregnant! And, not wanting her to feel bad, I even hugged her and forced a laugh. But the rude question swelled in my head as I drove away. Shame filled me for not having a  svelt body that carries clothes like a hangar. I've been exercising daily so, I railed at myself for not dieting, and for even wanting lunch.

1862 Luncheon on the Grass, by E. Manet

It happened earlier this year, last spring when I was touring a museum with my 28 year old son. A museum guard came over and wide-eyed, asked me in broken English when I was due. I was horrified and the dress that, up to then, I had enjoyed wearing, now felt like a cloth sack to be burned.
The worst: is my poor boyfriend, who is left picking up the pieces, and is forced to praise my body, even begging me today to lay on top of him. (I feel sure I would have crushed him flat).
He tries so hard to make me feel beautiful.
I think of the saying that you can only be victimized with your permission, and realize that I need a good comeback. Any out there? Any advice?
My advice to you is to NOT EVER ask that question unless you are in the hospital maternity ward.