Memoir about how adopting a dog helped a man get healthier

[Caitlyn]

Read in 2018 ish, but likely published before that. The man was apparently in bad health physically and mentally, and he made the decision to adopt a dog even though he lived in an apartment. I think maybe his therapist recommended it? Not sure. Anyway he ends up getting a wife and a good job and becoming very fit and healthy because of the dog. I'm pretty sure the cover had a picture of a dog on it.