I have to also wonder if the daughter is not afraid to like you again, given that in her world, you were in her life then gone. She may be scared to invest in you emotionally again. I will be honest with you. When it comes to relationships with people with children, I just don't think kids should be introduced any more then in a casual manner (ie: this is mommies friend) unless the couple knows there is a serious commitment there. Kids don't understand breaks ups, etc. So just not a believer in allowing anyone to get to involved in a kids life unless it's going to be permanent. I don't mean that as a slam towards you or the mother at all, it's just my personal belief. For now, I would keep your involvement in her daughters life casual. No overnight visits or anything like that. Not a part of the family so to speak. As Margy said, just give her time and space and let things happen gradually and naturally.
Play it down ...you are making too much of it... thats your ego ...so let it go, do not refer to the behavior the more you make of it the more it will become .Take a step back and let the dice fall where they may .....