<human>: Can you condense the text into a few key points?

I've known this guy for months. We're friends, but not very close. We text on rare occasions and we've hung out (in a group) a handful of times. 
Back in the summer, I was trying to figure out my feelings for him, and I had my friend help me out by talking to him about me. He told her that he liked me, but not to tell me. I tried asking him to a movie, but he turned me down. Later I found out it was because he started dating another girl. By then I definitely had strong romantic feelings for him. To my knowledge, this girl recently moved away. I thought this was an opening for me, but He seems to be showing interest in one of my other friends now. He has always shown small signs of being into me, like looking at me when he thought I didn't notice and speaking mainly to me, even if we're in a group, and this hasn't changed. Now, however, he also does this with my friend, and I can see my window quickly closing. 
What can I do? Should I just let it go, or try harder before I completely lose any chance I had?
<bot>: My crush used to like me, and I think he still does, but he's also showing interest in another girl. Move on, or fight for him?