She wanted to do more things, explore sceneries or probably just create new memories with him. He wanted to do them as well but with hesitations, he is so used to staying in. She probably wanted to discover themselves while he worries for the next shift.

She wanted to be surprised, she's a girl too. He realized that and thinks lowly of himself. She understands, kept going and kept loving. Then one time, she got tired.
He was busy and thinks that he does everything wrong. She can't say anything, she was caught up in the moment. They apologized for their wrongs and shortcomings.

They decided to call it quits.
They set each other free after 3 years and 5 months.

One last hug.
She cried, he cried.

It hurts but they have to say good bye.