Yes, it sounds like you are in a very troublesome situation. Don't blame yourself for it, these things do happen. I think that the best that you can do is make sure that your daughter knows that, despite anything, you will always love her completely and that she means the world to you. You can show this to her in any way, shape or form that will help her understand that you will always be there for her. As for your daughter's father, there is a saying that says "you can take the horse to the trough, but you can't make it drink". I think this is the case with your daughter's father. You could explain to him what he means to your daughter, but I'm not sure what effect this will have, as a relationship with his daughter has to come from within him as well as his daughter, this is not something that can be done for him, he has to make the effort himself. This situation obviously does not make things any easier for your daughter.
I really feel for you in this situation and I cannot tell you what the best thing to do would be, I can only offer the suggestion of focussing on your own relationship with your daughter, though, inevitably, at some point, you will need to speak to your daughter about her father (eg. when she asks you about him). Maybe you could, when you do this, lead her to see the beauty in the attention that she does receive from her father, no matter how minimal. Help her to focus on the positives in her relationship with her father, that she does sometimes get to see him despite a difficult situation.
I am very sorry that this is the best advice that I can give, I really wish that there was more that I could say to help. I really do hope that the situation eases for both you and your daughter!
This was basically a love triangle between the three of you; I would guess that your EX quite enjoyed "keeping" you and still being able to start something new. Triangles are never good, there is always someone who gets the short end, and it sounds like it may have been you and your daughter? I’m only going by the fact that you said you let him in and out of you life (and your daughters) for so many years.
He is the adult and if he wants a relationship with his child he would have to initiate it, I would talk to your daughter and just explain the situation as best you can, especially if he is like you say "devoted to her children" even though they are not his. THis must make your daughter feel horrible.
I commend you for leaving this situation; hopefully you can find a love to devote himself to you and your daughter. "That time has come"
