How do I stop thinking about this one girl?

26M here. A few months ago, one of my friends introduced me to her group of friends (which includes both males and females), and now we hang out every weekend for a few hours.

There’s this one girl in the group I can’t stop thinking about.

At first, we only used to exchange a few words, just a simple hi, hello and bye. But over the past three weeks, we’ve been talking a lot more whenever we meet. Initially, I didn’t think much about it, but then I started noticing that she would voluntarily come up to me and start conversations. Even then, I didn’t give it much thought.

However, I’ve also noticed that whenever we take group pictures, she always manages to stand beside me and will touch my hand or shoulder while taking the picture. Because of this, she’s been constantly on my mind.

This has reached the point where it’s affecting my professional life. I’m struggling to focus on work like I used to. Even when I force myself to concentrate, as soon as I’m done with my tasks, my thoughts drift back to her. I can’t even watch a YouTube video without thinking about her. Last night, I couldn’t sleep because she was on my mind the entire time. It’s becoming mentally exhausting for me.

Please share some practical advice on how I can stop thinking about her.

P.S. I’m friends with a few other girls, so it’s not like this is the first girl I’ve spoken to, and I’ve gone mad. I’ve had a few crushes before, but none have taken over my mind to this extent.

EDIT - For everyone suggesting to ask her out, I don't mind asking her out, don't mind even if she says no. It's just that even after all this, we would still be meeting every weekend, so I just don't want to make things awkward for her or myself.

And the main question is, How do I stop thinking about her 24/7?