annoying hating thots

So I used to work with this one chick and we used to get along and eventually became friends... So back then over 2 years ago is when I met her and at that time I was with a guy .... Little did I know she just got close to me so she could talk to my then BF... I found out that he cheated on me with her ... (FYI she's a married woman with a 2 year old son...) I met her husband we would go in "double dates" ... So I stopped talking to her and all after I found out she was with my ex... I felt like I had to her her husband but I didn't do anything I just let it be and moved on... So now I'm with my fiancé who now we're going to have a baby and I'm so exited 💕😻 I'm 11 weeks pregnant 
So my BF was using my phone and went in his FB he forgot to log out and I noticed that that girl was trying to talk to him... Just so you know every time I was taking to a new guy she just napped to find out who I was talking with and she'd well sleep with them and I wasn't going to fight a Thot she can keep them ... It just made me so mad that she's still trying to do the same ... Like wtf you have your own family why are you trying to fk up my own family ... I'm getting sick of her it's really annoying and immature of her to be consistsntly going after almost every guy i dated or talked with ... It's bothers me more cuz I'm pregnant and she clearly doesn't give a fk ... What should I do tell her husband Or what since now it's becoming a problem cuz I am at a high risk pregancy... Idk what should I do ?😞