Why is my crushes friend acting weird?

[the_one_1]

I met the girl I like and her good friend at a group event. I said hi to my crush, she responded then her friend said hi [my name]. This was a surprise as she doesn't know me or my name. Then, the full time after saying hi to me, my crushes friend kept on looking at me directly while talking to my crush who had her back facing me. My crushes friend never showed signs of interest to me only looked at me while talking to my crush/her friend , its usually my crush who points her feet towards me, her torso faces me, doesn't ask me questions all the time only if I ask a question to her she responds but never keeps the conversation going and looks at me from the corner of her eye. I noticed only once that both my crush and her good friend looked at me and I think they were smiling when I walked passed them. Then when I said bye to my crush, at first she didn't respond to it (like she froze) but then she looked at me (from the corner of her eye I think) and waved.

So what does this all mean?
Why was my crushes good friend acting weird/looking at me while talking to my crush?

[Devostator]

this is not friend, it's competitor!