Pretty low stakes question but tbh, I'm asking because I'm well aware that my decision making skills are being coloured right now over some heart-break I'm going through.

In dealing with said heartbreak I've been using games in my down-time as time fillers to keep me from thinking etc. I've recently gotten into a game called "Coin Master" with mostly current and former colleagues. It is an interactive game where you spon a roulette to win 'money' to win money to build items to complete a village before you can move on to a next one. More integral to my issue is that you can roll for options to either steal money from friends or attack their villages. You in counterpoint can spin for shields to protect your village but if your shields are all broken your items' levels are lowered resetting progress.

Now recently it seems like a former coworker is using this feature to target me. Twice now she's attacked me 5+ times consecutively basically resetting me to zero for the level. I was amused but perturbed the first time, really annoyed the second but I'm pissed off now because I just logged on and for the day she has attacked me over 20 times. Now yes for every successful attack she lands she earns quadruple plus money which is probably why she's using this strategy but it's so annoying and actually making me angry, probably irrationally so because my personal life is in the shits right now and I'm just trying to use this game as mindless entertainment/a distraction. 

I just sent her a message (it is 2 am here and my insomnia is in full swing so I had logged on to kill some time only to notice my village absolutely destroyed) and I sent her a message basically telling her to stop or I will delete her off Facebook because that is the only way to unlink her from my game.

We havent talked in years but I remember liking her enough that i enjoy getting the occasional life update from her on my feed the few times I actually log in but right now I just want to delete/block/the whole shebang but AITA for messaging her out of the blue with that and WIBTA to follow through?

Tl;dr: Former coworker I dont talk to anymore is ruining a game for me that I'm using as a distraction from personal life issues. AITA for giving her a one strike warning to stop or else I'll delete her off social media entirely to unlink her from my game?