<human>: I don't know if this is the right sub for posting this, so forgive me if it isn't. I've been taking french classes in a language school, and since last months, there's one girl in class that I strongly suspect is going after me. She usually tries to go with me when we do group tasks, and she's showing the usual non-verbal signs (playing with her hair, cute smiles, eye contact...) 

The problem is that she's 17 and I'm 24. I would never date a girl so young, so no need to warn me about this. On top of that, I know since last month that she has a bf around her age.

The thing is that while I never actively pursued her, I'm ashamed to say that I think I should have shown her that I was not interested. She's cute and I've been single since last year, so I think I kinda liked the attention. I know it sounds a bit lame. 

We are finishing the course now and all classmates are preparing a dinner party together, so I'm afraid that she could try to approach to me there. What should I do? Be nice and tell her I'm not interested? Tell her I know about her bf? Maybe not go to the party? I don't want to be rude with her because she's still pretty young and I feel partially guilty.

Btw, sorry about my english.

Give me a shortened version of the text
<bot>: There's a girl too young for my age that she probably likes me. How do I tell her that I'm not interested? Should I avoid the situation?