Quick rant because i’m confused

Okay so today i got a notification on facebook that someone had liked my profile picture and i open it up to see it was a girl who i’ve never seen before or anything and i was like weird but i let it go a couple hrs go by and i get more and more notifications from the same girl laughing at my pictures reacting to things i’m tagged in etc. and i’m like okay who the fuck is this girl and why is she laughing at my profile pictures so i go to her page its mainly private but i see that she’s in a relationship with my ex okay so my ex and i broke up 2 years ago i haven’t seen or talked to him since i’m married and have a 2 month old baby girl and have moved on with my life right so i am very confused as to why she is stalking my profile so i contact my ex’s cousin who i still talk to and the first thing she says is “oh god not you too!” so i’m like what do you mean? and so she begins to tell me my ex isn’t even with her anymore and that shes a psycho that she’s telling them that she’s having his baby that he needs to marry her that she is going to kill her self if he leaves her and all this other stuff including her wanting to fight his aunt at 4 in the morning one day because my ex had been ignoring the crazy bitch and she assumed he was sleeping with his aunt like ?? this girl has now literally gone up and down my facebook through all my posts i have since blocked her but she made another account and continues to do the same and i have no idea how she found my facebook or why she’s even going through my profile and i have no idea how to get rid of her since i’ve already blocked 2 profiles and not only that but she some how got ahold of my husbands snapchat and added him he didn’t add her back he just blocked her but my husband doesn’t have his snapchat posted on anything so we have no idea how she found him so now i have made my profile completely private and idk if she will continue to annoy me but she hasn’t tried to message me and i certainly am not going to message her about anything because i don’t want to get dragged into her demented shit she has going on!