A very sad song

Just downloaded this song today. this song is so sad and touching.
Heres the lyrics for the chorus:
想念是会呼吸的痛
它活在我身上所有角落
哼你爱的歌会痛
看你的信会痛　连沉默也痛

遗憾是会呼吸的痛
它流在血液中来回滚动
后悔不贴心会痛
恨不懂你会痛
想见不能见最痛

By MingChin