.....We used to love one another,
Give to each other,
Lie under covers so,
Are you friend or foe ?
That's a piece of lyric Friend or Foe by TATU.
Sometimes in life, there are no fully people who like us. There are some parts that don't like us. It's normal. Everything happen by reasons. Both like or dislike. Even when we think someone as a friend, she/he may not necessarily able to be trusted as a friend.
They talk about you behind without you realize that, why or what. Even possible, they are also preparing evil-plans to bring you down from your position. Even The Prophet Salallahu'alaihi Wassalam is inseparable from those who envy and hate him, moreover us.
So, if you don't want to get hurt, you should determine who is friend and who is foe... It doesn't mean we prejudiced someone before. Just to keep you more sensitive on people around you.
-Regards-