Hi Sam. You have a difficult choice and dude, it suckssuck but how you handle it will affect both you and your daughter. 

At this point, your marriage is over but being a dad means putting your child first, even if she's not your biological daughter, she is your daughter. Remind her that you love her and are there for her and make sure you are. It will mean accepting the humiliation that you lost your wife but no one said being a man was easy. Make sure you take time for yourself and never lets our (ex) wife's actions affect your happiness set seeing your daughter. 

They say say the best revenge is living well, then live well. 

Hey buddy, firstly got to say for you to take on another mans child as your own any is a huge gesture for any woman or child. That takes a lot to do and by the sounds of it you have a lot of love to give well done on that front.

However reality check as much time and effort you put into that child ultimately that child is NOT yours and is basically an extension of your (hopefully) soon-to-be ex-wife!

Who is (unless that child's father is around) is solely responsible for her child the fact that you have a void in you that this child fills is something you will need to address. But the way to do that is to leave this woman and HER child alone she left you which basically means she does not want you in her life. And if she is telling you her financial issues then basically you are her pimp her sugar daddy her toy thing as she is trying to use your loving nature to trap you into providing for her. Dude if you have that much to give then I would say she is the one that ultimately losted out.

Walk away fon her and her child. It sounds like you should really be a woman who loves you unconditionally who wants you to be the father of her kids and well this ex-wife is stopping you from finding that person and starting your own uncomplicated family.

Dude regardless of how you feel that mother, that woman and that child should no longer be in your life.

Its a hard fact to swallow but you need to move on block her from your social life and your heart in order to heal your only setting yourself up. If you stayed who is to say if this slut has another child that it will actually be yours. What happens if you stay with this slut then come to your senses and start blaming this innocent child for being a strong reason for you staying. 

It is such an unhealthy situation to be in I hope with space and time you see that moving on was the best thing to do. 

And sorry but this chat about oh I want to talk to this guy look he never sucked his own dick she did with her eyes open and fully knowing the consequences to both you and her. And her daughter too but I'm guessing she knows how soft you are on her daughter and the idea of a family. 

Dude I hope you leave and find a real woman and have your own child that bond you share with this woman's child is nice but with your own child and loving wife will greatly surpass this slut and all her heartache

GL

updates please

I wish you could see how your story sounds to everyone in the world who is not you. Then your decision would be easy. Best of luck to you.