At least for now you don't. But what if that changes? And what if she stops giving you the attention and then you feel rejected when there was no rejection?

And think of how you felt when you realized that all of your attention that was given to the other girl was for nothing - you felt used and heart broken. Are you seriously ok with the idea of doing that to someone else just to make yourself feel good? Really? You can do other social things where you can feel connected without using someone.

So if you ask her, there will likely be some awkwardness and embarrassment - but you can provide her a chance to know you aren't interested and thus not let her waste her time, and you can spare yourself any future attachment you may form.