不是我不能说我爱你 is not that I can't say I love you.

而是想你痛彻心脾 It is after missing you deeply into my heart

却只能深埋心底 I only can bury it in my heart

世界上最遥远的距离The furthest distance in the world

不是我不能说我想你 is not that I can't say to you I miss you

而是彼此相爱 It is when we are falling in love

却不能够在一起 but we can't stay nearby

世界上最遥远的距离 The furthest distance in the world

不是彼此相爱 is not we love each other .

来源：未知