From the album Blue Again, but That's Life
"That's Life" is a popular song written by Dean Kay and Kelly Gordon and first recorded by, Marion Montgomery in 1964 https://www.youtube.com/watch?v=qaSUXRSxrDU.
The most famous version was recorded by Frank Sinatra, released on his 1966 album of the same name. Although Sinatra's vocal arrangement was nearly identical to Marion Montgomery's vocal arrangement, Sinatra gave credit to O.C. Smith, which was a completely different vocal arrangement. O.C. Smith was second to record the song (1965).
Both the album and the song proved major successes for Sinatra.