Why do girls say things they dont mean or act like your a friend when u dont wanna be?

All right i asked this girl out like 2 weeks ago but she said she had trust issue n didnt want bf so she said it was cool if we were friends.. but the thing is i try talkin to her bout stuff n she really off ish lately n when i try to get her to talk she shy away from things or just doesnt respond then if i ask her if there ne thing she wants to talk about she just say ummmm..not really. do this girl really wanna be my friend or wut cause i would like to be hers but if she dont wanna talk then how r u suppose to get to know someone if u dont talk...should i give it time or just move on