The only thing divorced parents need to communicate about, via mediator or however, is important information regarding the kids. This can be done without having a personal relationship. It really doesn't have to be any more involved than communication with your child's teacher, which in my experience, is often done via notes in the child's agenda. There's never anything personal and you never have the teacher over to your house, nor are you expected to.

This guy is engaging in a personal relationship with his ex. As such, you should walk the other way unless you want to be involved in his love triangle which is surely to develop from all this.

I agree, you should not have a personal relationship with your ex, nor should either of you be meeting each other's needs. This only serves to delay getting over each other and hurts current relationships either of you are trying to have. Ideally, any communication done with regards to the children is minimal, cordial, respectful. My kids' dad and I have been able to accomplish this over the years. We have gone in on Christmas/birthday presents for the kids on occasion, have attended our daughter's wedding, and the kids' grandpa's funeral (last week) without any problems (other than his new wife getting drunk at my daughter's wedding and flirting with my fiance...who handed her back to her husband). Respecting his new wife's wishes, I do not ever call their house. My kids are adults now so if their father wants to contact them he can call them on their cell phones directly...however, he has called them at my home when they were there because their cell phones don't work there. If I need to communicate with him about anything, I do so to him AND his wife by email. We live in a small town and never bad mouth each other, and try to show respect for each other because we are our kids' parents. Not everyone can be as successful at that though, sometimes the person you're divorced from is such a heel, such a crumb-bum, nothing works but restraining orders, and strict adherence to custody agreements. In our case, we didn't have to go through support enforcement, and I left it up to the kids if they wanted to see their dad whenever they and he decided and it all worked out rather well. Too bad the marriage wasn't as cooperative as the post-marriage went!

I had another thought about this last night. This man SydneyT is dating is not here on MB asking for advise. He is likely unfamiliar with MB or, on the off chance that he is, he has rejected it based on his behavior (relationship with exW). In either case, he's not a great candidate for an MB-based relationship as he shows tendencies that counteract important principals here. SydneyT isn't married to this guy, so she has no reason to try to preserve this relationship. It doesn't mean it's easy to let him go, but there are men out there who, even if they've never seen MB before, are more likely to work with this program.