His ex is horrendous😣

I don't know if I just need to rant or I need advice I don't know! it's just getting to me now! My partners ex is a horrible vile disgusting human! when myself and my partner met we met at the hospital he had a work related injury and I was having a scan to see if the remains of my baby from my miscarriage had passed as the miscarriage was very complicated, anyway! My partners ex had his baby while we were together they had split up early on in het pregnancy, after she gave birth to my partners son she had decided she had the right to tell me I deserved my miscarriage and on another occasion told me I wouldn't know what it's like to be a mother, I have pcos and have difficulty falling pregnant, so this hurt me deeply when she said this as you can imagine, she has now took to turning up at my partners flat unannounced and demanding money and guilt tripping him for being with me when she turns up with the baby, he's been in hospital a few times because she smokes weed and still breast feeds (this makes me mad) he has difficulty breathing now and a few problems and coming up in facial rashes but will not tell the hospital she smokes weed, and last night was one of the worst me and my partner were at mine cosy on the sofa watching tv when he gets a phone call from her, on his nephews phone so she is at my partners (we reckon she's now sleeping with) claiming the baby has meningitis and that the baby is so I'll my partner saw the baby before her come to me and he was perfect jumping and smiling and laughing and crawling but magically the minute he's with me she is telling him he has meningitis and then said that my partners nephew agreed etc she called 111 (if the baby did have that they would have called an ambulance) but she gave 111 my partners number my partner explained and said the baby was with his mother, anyway my partner got back for her to then say instantly oh he is fine now she admitted she lied my partner told me she lied and I instantly got so so angry about it! She won't stop doing it! She guilts and manipulates my partner 24/7, my partner has very bad anxiety and depression and she just won't stop! I just don't know what to do she slated me about not being a mother and how she's glad I miscarried and I deserved it and then said the same about the baby me and my partner lost last month, I don't really know what to expect from this I'm so upset and angry I'm not wrong to be am I? I just am lost right now she leeches off my partner for money for herself physically hits and screams at him in Front of the baby and it breaks my partner that his ex does this so the baby sees it all! I'm so angry sorry for long to post I just needed to rant!