I had this happen as well. If you check out a topic called “annoyed and a bit creeped out” you will see how I realized that the former AP was stalking my Instagram account via a second account she had created for her pet.
For about 6 months I struggled with whether to make my account private (my Facebook already was) because it pissed me off that I had to make yet another change in my life, because she wouldn’t butt the heck out of mine. But another poster pointed out that it seemed to be taking away my ability to just “be” and I realized she was right. Plus, it was making me think about the AP EVERY time I saw her stupid Instagram account in my Insta Story list... but otherwise I was often able to go days without thinking about her/it. I realized that by not changing it to Private, I was allowing her to make herself relevant in a way she hadn’t been for a VERY long time. I turned it private and it was VERY freeing!
BS - Female
Married 27 years, one adult child DD May 2016 “When we are no longer able to change a situation, we are challenged to change ourselves.” - V Frankl