Artistic License Gone Wild

So yeah, I've been dating this woman named Eliza for about six months now. She's an artist too, which is dope because we understand each other's passion and shit. But there's a twist: she has these secret kinks that have nothing to do with her art at all. It's like they're separate entities inside of her or something. She asked me one day if I'd ever played DDLG before, you know, Daddy-daughter dynamic kind of thing? And I had to say no because honestly, it felt a bit... out there for me. But then she said we could try it out and that got my curiosity going, so okay, let's experiment. We started off slow with some light roleplaying stuff. She wanted to be treated like a little girl sometimes, which meant I had to act all protective and disciplinarian. It was weird but also kind of hot because we're both adults here, right? So it wasn't that bad to pretend. But then things escalated in ways I didn't expect. She started asking for more serious discipline scenes where she would be grounded or punished like a kid who broke the rules. Like one time when she came home late from an art show and pretended she got into trouble with her parents for not following curfew. It felt strange, man, but also kind of thrilling because I didn't want to let her off easy. The problem is, we've both hit a wall now. She wants more and deeper involvement in this dynamic, which means I'm supposed to be stricter and more demanding as the 'Daddy'. That’s not something I’m comfortable doing or feeling right now. But telling her that feels like saying no to an artist who needs their muse, which is just... ugh. So here I am, trying to figure out if I should push back on this, end it early before it goes too far, or try and find a middle ground somewhere in between. It's complicated because I love her for real, but this whole dynamic isn't really me. And that’s the kicker: what happens when you start playing pretend and your character gets too heavy to carry? Am I the asshole for hesitating here? Hell if I know.