<human>: Could you distill the essence of the text into 1-3 sentences?

We're both seniors in high school and she's been my friend since 7th grade.  I started developing feelings towards her and recently told her how I feel, but she said she likes my other friend.  I wanted to just let it go since we're seniors and going to different colleges next year, and I didn't want to screw up being friends with her.  I only told her because she was acting really flirtatious with me and begging me to tell her who I liked.  Turns out, she likes my friend who's not interested in her at all.  Now that I know how she feels about him, I notice all the time that she's flirting with him.  We weren't exactly best friends before, but now she has noticeably gotten more friendly with me and started calling me her best friend.  I don't know if this sounds selfish but I'm really not able to deal with this.  I can't just be friends with her now, especially when she flirts with him right in front of me and pretends I don't feel anything towards her, it just doesn't feel right to me.  What should I do?
<bot>: told my friend how I feel about her, she likes my other friend, now pretends I feel nothing towards her and wants to just ignore it.