So, girlfriend of a few months and I are texting when she says

"You're so sexy to me its unreal. Like, sometimes I don't even know why you're attracted to me, you could get someone better."

So, clearly she's fishing and expects me to start gushing and telling her how amazing she is etc. I'm not in the mood for this game so I offer

"You're what I want."

Not saying I can't pull better, not commenting on her appearance just "you're the decision I made and that should be good enough." So she tries again

"Yeah, but you could do better."

Again, noncommittal

"Why do you say that?"

Obligatory "I'm not that pretty." We both know this is obvious bullshit. I wouldn't keep her around if she weren't hot. Solid 8.5, but I digress. So she tries a third time

"You could get a hotter girl. I've never felt like the unattractive one in a relationship til now."

Getting tired of this I offer

"You're sexy as fuck IMO. You've just been slummin' it 'til now. Welcome to.the big leagues."

More stupid bullshit, we watch Blue Valentine (shitty movie but great educator on how women really are and why it doesn't pay to be a beta) and when its over she says she "wanted more" out of the earlier conversation. I decide to show my hand

"Well, what were you looking for?"

"Something different" she says.

I tell her she's right, I could get a hotter girl, if there was one, but I already snagged her so there's nowhere to go but down. She says she'll keep an eye out for the prettier girl so she can send her my way.

Did I handle this properly? How could I have done better? I'm usually pretty good with frame even though she's a fucking master shit-tester at times, but this honestly threw me for a loop. She would not fucking drop it, but I wasn't about to tell her I couldn't do better. I feel like I lost the upper hand at the very end. If it were a plate I'd have just told her not to worry about her looks 'cause I really just keep her around for the good head, but not sure that's a good move within the confines of a relationship. Thoughts?