I care about you,Do you konw?But you told me:so sorry!Can yo

grieve是动词.不能这么说,把grieve换成sadness.这样说好点.
Do you kown that I care about you?But you told me that:"Can you understertand my pain and sadness?"
译文：
我是关心你的,你知道么?可是你却告诉我：很抱歉.你能理解我的痛苦和悲伤么 .
我在乎你.I do care about you.
（加个DO表示强调.语气更坚定）
I only care about you.（我只在乎你）
呵呵,希望对楼主有用