Hi D, (long time but I check in occasionally!)
Having been in your husband's shoes, I can understand why he wouldn't want your new man in your daughter's life. I definitely have a bitterness towards the woman my ex cheated on me with and subsequently got pregnant before our divorce. But I know that is my own pain, not my daughter's.
On mother's day, my daughter gave me a flower pot and said her daddy's gf helped her make it, along with the card. My initial response was, "ugh I wanna throw it away". But seeing how it was from my kid, I couldn't. And I sat there looking at it and thinking, if this woman could go sit there with my kid and help her do this for me, when she knows that I would spit on her if I saw her on the street, she must have some inner strength and compassion that I am lacking at this juncture.
So I texted her Thank you, happy mothers day and wished her the best. She responded with the same. It was the nicest communication I have had with this woman since I found out about the affair.
I know that my bitterness will not immediately disappear, and I still do not respect this person, but dammit if she didn't just prove that she is a better person by doing that. And if she can continue to give me the space I need to raise my child, and respect that my ex and I are the only parents of my child, and that she does not belong at parent meetings at the school, or doctors appointments, or other parent related activities unless specifically asked by both of us, then I think we might someday reach a point where I do not want to spit on her when I see her or yell obscenities about physical appearance and sexual habits.
There really is no need for the other person to try and push their views on the upbringing of the child. If the child already has two parents who take active measures in raising the child, then the third is inappropriate.
There are other ways to influence a child and help with upbringing. Your new man is not her father. He can be a role model in other ways though, and I know that you two will find that balance.
Good luck and take care! I hope your hiatus is almost over! LOL.
Taylor