Aijohn had clear distinctions between right and wrong, and discernment between good and bad.
Hailey and the lab may be his life for many years, but he could not allow his marriage to be ruined just because of his dream. He felt sorry for his loss as he looked around but before he could allow himself to fall, he walked away.
Hailey followed him through her eyes until he disappeared. Tears fell down her face, but these would be the last. Her life didn't end at the vehicular accident during the peak of the storm, it wouldn't also end at the loss of someone who used to be her husband. The fact that he walked away and did not even make a plea, meant that he could no longer be hers.
If she would insist, the law would make her claim him back as rightfully and legally hers, but she did not need an unwilling heart. She knew she had to let him go.