I would suspect there's more than just pop culture creating the problem.

Do I have this? When you were thirty-six, you moved in with a woman, and her three year old daughter....and after sixteen years, ...you and the mother are no longer lovers, as in a couple, but you continue to live in the house. And after sixteen years of being an active, and fun, father....the daughter has turned on you.....am I missing something???

Teenagers can be a trial for sure

This is temporary. As a teen, her developmental job is separating from her parents. It's hard for parents.

@ToolGuy is correct.

"I hate you!" my daughter Claire raged at her dad and me when we said no. "You are not my parents!"

That didn't last. After six weeks, she came back. "This is temporary," was my mantra when Claire was a teen and in her early 20s.

At 29, Claire is respectful, appreciative, thoughtful and loving.

Sorry that sucks. Teenage girls know everything and they are mean.

Tweenie bloopers. Can't live with 'em. Can't shoot them and their Taylor Swift records off in a rocket ship to go live in the freakin' moon. What's a guy to do?

This is a very tough situation for you and it cannot be easy. Try to make allowances for her youth, and like @Athena I believe this will only be a temporary blip in your relationship with your daughter. Even if she were your biological daughter you could be getting this treatment from her at the moment, I know lots of parents who are treated with scorn and derision by their teenage children...I remember my husband and I seeming to be a constant embarrassment to our boys, who acted like assholes for a period of time. Try not to let this get to you too much, if you can discuss it with your ex wife ...presuming you are on good terms, as you’re still under the same roof, it may be helpful. Best of luck, and just keep trying to be a good Dad.

She's 19. Its tough at that age. I raised my daighter starting at 7yro.
Give her space to figure it out

You lived through very difficult teen years with her. These are the ones during which, in the mind of many teens, they know everything, parents don't know anything and are super embarrassing... and life to them seems unfair.

They usually circle back to being more appreciative once they mature and (with hope) understand why their parents said and did the things they did.

This is hurtful because, although you're no longer with your ex, you raised her daughter like she was your own. The best thing you can do, I think, is let her know you're there, disagreements and all. Once she takes a few hits in life and maybe when she has her own kids, she'll start realizing what a great father figure you were to her.

One piece of advice I can offer, which I believe is of value to all of us, is that whatever advice you have for her, make sure it's delivered in the same way you'd like to receive advice. If you can't have things in common with her, you can always be supportive and make her realize you've always cared.

Sounds like a difficult situation all round.