She's been setting old photos of me (where I was nassively obese) as the display pictures in group chats. I've been agreeing and amplifying or ignoring for months while she did this on/off because I honestly didn't give a shit (usually she changes the group pic again to something else, then erratically back again when she is bored).

It's beginning to get on my nerves though, it's like she's trying very hard to get something out of me with this and I don't understand why she's so persistent. what's the next course of action I can take to turn her off of using my unglamorous pictures, in any capacity, for group chat display pictures?