He loves her. She loves him back. There should be no problem, but no, there is a problem. She's still living in her past, she's not willing to let go of her past and that makes it harder. 

Though he never give up before, he finally thought of moving on and let her go. But can he really do it?

Will she be able to move on and accept his love?

I shook you off, who begged and clinged onto me

But looking back, I want to turn back time

Without you, I can't do anything

I miss you