I would not use humor with your friend at this point. I would just calmly tell her point blank that you have no desire to drink ever again and that you don't appreciate being taunted with it. If she doesn't stop, stop hanging out with her.
I had this exact thing happen to me when I was about 15 months sober. My oldest friend that I had known since we were 5 years old asked me when I was going to start drinking again. I told him I was shooting for never. He didn't understand, he said it seemed like it was easy for me to quit. Once I explained just a little bit about it to him (and in about 60 seconds) he understood. And he never asked again.
I also had my first cousin say to me at a wedding right about that same time "If getting sober is going to make you this skinny, I think you should start drinking again." He was not joking. But I'm close to him still and he has never mentioned anything about it again.
They don't understand it. They aren't alcoholics. These things irritated me at first until I realized they had no way to understand why I wouldn't drink anymore. And I've been asked the same thing even now by people close to me even though I have been sober a long time.
With your friend you can just "lay down the law", but your husband is a little touchier situation.