Heh, it sounds a bit like my mom has been moonlighting. I've always been conscious of my weight - my mom used to keep on going on about puppy fat, but looking back at photos of me as a little girl, I was a scrawny little thing.
As I got older, she would keep saying stuff like, 'you carry all of your weight on your legs', and 'it's a shame, you've got such a tiny bust and waist, you're like two different people stuck together'. I got so self conscious that I'd only wear ankle length skirts.
When I was 19, encouraged by my best friend, I bought a knee length dress. My mom saw me wearing it, and said, 'ooh no love, you've not got the legs to wear that'.
In my early 20s, I became bulimic. I finally started getting compliments from her, whilst my friends became desperately worried at my protruding ribs and sternum and pallid skin.
I ended up having therapy, and realised how much my mother had damaged me. I'm now genuinely a bit of a tubster (turns out I have PCOS and hypothyroidism), and I do want to lose weight, but sensibly and to be healthier, rather than to appease my mother's sensibilities.
Despite knowing that I've suffered from an eating disorder and the aforementioned conditions, she still asks me 'how much are you weighing?' every time she sees me. She asked it two days after I gave birth. She also said, 'After you, fatty!' when I was 8 months pregnant!
She's obsessed with everyone's weight though - my brother, his wife, his in-laws, our dogs...