Why is it that when you finally love someone you always get your heart broke?

You may think you loved him/her, but did he/she really love you?

It may hurt to lose someone that you love, but you cant spend the rest of your life hurting.

How can i forget you when your always on my mind,
how can i not want you when your all i want inside,
how can i let you go when i cant see us apart,
how can i not love you when you controll my heart