She's a main love interest, and she's a whore. It's not complicated.
Just admit you're a cuck with no self-respect and move along
Depending on how her story will go, she could end up putting a stop to that source of income. And she's doing it because it's a quick buck, and guaranteed pay.
Income she needs to pay the rent AND pay for her dad's drinking habit. She has nowhere to go as of right now so she fell into that lifestyle. And you could very well choose to just be her friend and help her get out of that lifestyle. You don't gotta date her. But if ya wanna bash her for something she was kinda forced to do given her particular circumstances, announce you're a self-centered asshole without saying you're a self-centered asshole, am I right?
Guessing you're one of those people who can't have a female friend without fucking them.