AITA for threatening my ex's wife?

I (25 f) have an ex (31 m) from about 2 years ago who has a wife of 9 years and a 2 yr old son. He did tell me he had a child from a previous relationship but he lied about being married.

We broke up when I caught on to too many red flags about his relationship with his baby mama (actually his wife), and went no contact. Sure enough, I was right. A few months after we broke up his wife reached out to me on Instagram, having found pictures of him and I in his phone, and I gave her the whole story. I felt so guilty, as my actions had indirectly hurt her, while also feeling mortified having been "the other woman." She felt too embarrassed to tell her mom and sisters and I felt empathetic to her position, so I let her reach out to me when she needed support for about 2 months. I tried to encourage her to go to therapy and make a plan to leave him. However, it got to a point that I wanted to move on and not talk about the situation anymore. I told her that I have told her everything, what she does now is up to her, but I didn't want any involvement so i can't communicate anymore, then I blocked her and made my personal account private. Then she flipped a switch. She must've confronted him after this and he must've manipulated the story to her because she sent spiteful, mean messages after that, each message from a new, fake account she created. The messages would include calling me names and accusing me of trying to get back with him, which confused me because I had been on no contact with him since we broke up. She has been doing this on and off for the past year and a half. I had not done anything to stop it because everytime I considered taking legal action, the messages stopped. I hadn't heard in awhile until recently, she now has contacted my current boyfriend (25 m), having found him through my business account (don't know how she found out that was my business account) telling him I'm a bitch, he deserves better, and to break up with me. I filled in my boyfriend on the situation long before this, so he has my back and is supportive of however I want to handle this. I had him reply to her that if she contacts either of us and anyone associated with us that we would take legal action, but now I'm thinking that would affect their kids who are innocent in all of this. AITA?

Update:

I went to the police, who unfortunately said that due to their residence in Mexico and their usage of fake accounts, makes it near impossible to get a restraining or no contact order on either of them. BUT... it's okay because sounds like karma hit him. I called out the most recent fake account for being insane and harassing my boyfriend and it turns out some of you in the comments called it... the recent harassment is from my ex who was pretending to be his wife 😳 WTH. His goal was to try to ruin my relationship because... his wife left him, took the kids, and already has someone knew. AND his work visa wasn't renewed for whatever reason, so he won't be coming back. KARMA. Knowing that neither are a physical threat to my boyfriend or I is comfort enough for now. I'd like to hope the messages will stop eventually but it definitely won't come between my boyfriend and I.