Two years ago, Matthew Proctor dropped to his knees in the Afghan dirt and watched his best friend bleed to death.
These days, when dreams get disturbing or guilt eats at his gut, there is one person the former Marine corporal is likely to call: Thomas Rivers Sr., his dead friend’s father.
When Mr. Rivers, 60 years old and a pharmaceutical executive, feels himself sinking into black depression or misses the pleasures of raising a son, it is the 24-year-old Cpl. Proctor he confides in or invites over for a boat ride. “He lost a best friend, and in a sense I lost a best friend as well as my son,” says Mr. Rivers. “That is a bond we share.”