Agree with you-- your WH could do a plethora of things to grow up. Yup! So could mine, ay yi yi!
A FB page/website for bub may not be your thing, but I kinda like it for me, actually...
I met with my lawyer today to hammer out some things. I have all these grand ideas for my divorce ("He will never introduce her to girlfriends without my permission" and "We will live, hopefully, far apart, and he will see her once a year" etc etc.) And the lawyer keeps reminding me that the courts are pretty balanced and that I need to make my divorce enforceable. (I could throw some things in there that are hard to enforce, but then if SBTXH breaks them or if he takes me to court to contest... I won't really win!)
All this to say... my advice is to give him access to bub. If you're emailing him back, maybe cc some other family members to make it less personal. I don't know.
We have to do the hardest freaking thing-- act like things are "okay" with these men we love who have hurt us so deeply. But they can know it's not "okay" by us just staying extremely impersonal.
Someday hopefully our daughters will understand our sacrifice.