My friend never calls?

[Edward S]

My best friend and I are really close, we even say the same things at the same time and like the same stuff but when we first became friends she called alot but for the last like 6 months she never calls me and I call her. At school she talks to me alot, she's usually truthful to me but lately she hasn't been, I don't understand. She still thinks of me as her best friend and we hang out like crazy at school. I aksed her over one Friday and she told me her parents said that they were doing something with the family but I found out she had already had plans with a dif friend, I don't understand why she didn't just tell me, I wouldn't of been mad, I like to hang with different friends once in a while too. Why hasn't she been tellin me things, or calling, It's like once we leave the school we don't talk or hang, we go to each others house every cople weeks, alot less than we use to. Should I stop calling her and see if she gets what I'm feeling. I don't want our friendship to fade.