<human>: A little backstory, Katy I had known each other back in sophomore year. We hardly talked to each other but we knew each other were good people. She is around 5'4 and is super smart. She is also a peer leader and us really nice. I never made a move on her because I thought she was out of my league. Two days ago, my friend Anna, Katy's friend, asked me if she could tell Katy I liked her. I said sure. Katy had said to her, " why didn't he tell me sooner? I would have gone on a date with him if he asked. He seems like a really nice guy" ( Facepalm of epic proportions). Although now, She is talking to another guy. One that I know, but not too well. They are not together yet though and he also posts stuff on other girls insta like OMG you're so hot. And fire emojis.

What do I do? How can I let her know? What can I do to prevent her from dating this dick?

Provide a brief overview of the text.
<bot>: Girl I liked but didn't make move on. Turns out she would have gone on a date. Now she's talking t another guy. Who do I do?