Why doesn't your crush ever say hi to you when you see her but when she's in a group of friends she tags along quietly?

if she fancys you its probably cos she's too scared to talk to you because she might not know how you will react... why dont you start off the conversation first? then she might feel that you are cool. if you fancy her she might think ur weird or maybe she doesnt know that you fancy her yet. same again talk to her!! hope that helps :)