Maybe that's how the word "regrets" works.

You find him irritatin for him to rant at you .
You find him annoyin for the quarrels .
Untill you told yourself that one day you gonna leave this irritatin and annoyin guy.

But that wasnt all.
This girl knew he was in agony with her too.
This girl knew that he was tolerating every second with her.
She wanted to end his agony.
She dont want him to be so so so sad over this possibly-everlasting-relationship

Too, she was guilty all along bcuz her parents trust her so so much.

You've got days/months of likin him,
You've been with him for about 4 months.
But it took just one day - and its over.

He was gone and then you realised how important he was.

Humans tend to not cherish the things they had,
Until it was gone.

I knew this all along but i never had a chance to feel for it myself.
Sometimes its not that humans are being inconsiderate, its just that they do not know how it feels to be like.

Now I know.
Too late.我好想你