假如你是某报社“Heart to Heart” 栏目的编辑，专门负责解答读者生活中这样或那样的困惑。仔细阅读下面Xu Ling同学的这封信，然后以栏目编辑的身份写一篇回复，对Xu Lin 同学存在的问题给以解答或提供建议。
Dear Editor:
I am a Senior 1 girl.I use to have a lot of friends.But they have left me,one after another.I don’t know why.
Some of them said Iam a selfish girl,but Idon’t know what I have done wrong.Could you help me?
Yours,
Xiu Lin