Hi there, new to this site myself. I am the new other half of my partner who has a dd and a ds. My ex came out a very aggresive, manipulative and controlling relationship.
We have done everything we can to make sure the idea of their mum with a new friend/partner(me) has been gently fed in over a couple of months, by doing things together, being interactive and gently getting them used to me being around. E.G. I get up at 3.30am every time I stay over so the kids see me on the sofa every morning. So really doing everything we can to keep the kids away from our personal time. Unfortunately her ex has never met me, and does not know what I do to protect the kids from confusion, when he sees them, he feeds them stuff like "If you misbehave enough, you'll split mummy and her new boyfriend up, and me and your mummy will get back together.. You'd like that wouldn't you??"
Even though I find it sick he's playin with those kids emotions, he is still and will always be there father. I've been wanting to meet him to say, I'm not a bad person, I'm not harming your kids in any way, infact doing everything to protect them, but my new partner knows he will react violently. My view is (1)I'd rather meet him away from the kids if that does happen (2)I think it could quell a lot of his frustration if his mind was put at ease, even a little bit, so I can understand your situation.
I 100% believe you should see who's looking after your child, and let her decide what is true and what is not about you and vice versa, but you must be ready to accept she might be bringing real value to your daughters life and you can actually be a part and encourage her, after all it's all about the childs future.