Concerns about Ex-Wife Introducing New Boyfriend to our Children

Hello everyone!

Wanted to come on here again to explain my situation and see if anyone else has had similar experiences and/or tips!

I previously posted on here about my high-conflict custody situation a while back, and I wanted to share it to serve as the background: https://www.reddit.com/r/daddit/comments/1iu1owo/missing_my_kids_after_separating_from_their_mom/?utm_source=share&utm_medium=web3x&utm_name=web3xcss&utm_term=1&utm_content=share_button

While my ex-wife and I are on generally OK terms, it is often very difficult to communicate with her about things I want to do with our 2 and 5-year-olds, as she tends to become extremely defensive and abrasive. This was particularly noted when I had let her know that I was thinking of taking the children to Puerto Rico for 5 days as part of my summer vacation. Keep in mind that I have taken the children to multiple destinations around the U.S. by myself before, with no issues, and we both share equal legal custody. She eventually had a meltdown about it and was being unpleasant about it until she calmed down and apologized for her behavior.

About a week later, she tells me that she would like me to meet her current boyfriend, whom I kind of knew about but never really inquired about. We had both agreed to have each other meet our partners prior to introducing them to the children. Neither one of us has yet introduced our partners to the children, with now almost 2 years of separation. This is about the 3rd or 4th boyfriend that she had requested me to meet. All her prior partners were odd in the sense that they were borderline obsessive or completely disinterested regarding the children.

When I asked about basic information about this new boyfriend, she revealed that they have been dating for about 4 months so far and have previously dated. This threw me off a bit as my ex-wife and I had been together for about 4 years, and when I asked who he was exactly, she told me it was the ex-boyfriend she had cheated on back in 2019. I had known my ex-wife since about 2017, and we did not actually start dating until 2020, so I do recall all the negative things she told me about this boyfriend back in 2019. From what she told me herself at that time, he was lazy, did not have a job, was mooching off of her, clingy, and just overall unpleasant. These things are what prompted her to cheat with a random guy from a cruise, as well, which led to the dissolution of that relationship.

Knowing that this was the same guy she had spoken so negatively about years ago, I expressed my deep concerns about having this type of person around the children. She went off to tell me that he has "changed" and is a "new person", which, of course, I am extremely skeptical of. When I did express my concerns about this, she became defensive, harsh, and started to yell about me not being open-minded, being arrogant, and thinking I am better than him, etc. I simply told her that my concerns are valid, especially with someone with that known and confirmed background. The next day, she again apologized for her outburst, but I definitely know that this will not be the end of it. For additional context: I have a partner that I have been seeing for about 7 months now, and she is a wonderful person, but I do not have any plans to introduce her to the children until much, much later to ensure I feel completely confident in her.

Has anyone dealt with this kind of situation before, or have any recommendations?