No Pigeons

I Just wonder why girls get madd when you are flirting with other girls. I know that sounds stupid but let me explain. Say you like a girl and it seems like she likes you too but you dont know for sure and you dont wanna ask her out because you are affraid of rejection. She just goes through each day teasing you and leading you on and you cant help but to give into it. So when you finally say " I cant give into this anymore" and you go and flirt with another girl, the one you like finds out and gets madd. On the other hand say you are not affraid of rejection and you ask her out and she says no, because she doesnt really like you shes just teasing you, the next day shes acting wierd and like trying to stay away from you like your a freaking stalker or something. How about just when you are flirting with a girl but actually trying to be nice and do the right things to make a girl your girlfriend and shes not giving you any signs or anything saying that she likes you or even that she wants to just be friends. Shes just giving you mixed signs and you are going crazy because you dont know what to do and if you do act on it you look like an idiot if she doesnt like you like that and then once again the next time you see her she acts wierd quarenteed. I just want to know why poeple say your a "Player" or something when your just trying to find someone to date. I mean how are you suppose to find someone without flirting with them? Also how are you suppose to know when a girl really likes you or when shes just teasing you? Ladies please help me out. Thanks. Peace.