Three years and three years
Three years spanned it
The happy time three years ago was a huge wound in their hearts. Although it has scabbed, the pain is always there, reminding themselves all the time that that person is always there.
When they met again three years later, she approached him again with timidity and apologies.
He and she were once the good things in each other's hearts. Their ending will be whether they hold hands again or end up in separate worlds.