The longer a person is not present, the easier he or she is to forget about. A: "Is Carrie really dating someone else now?" B: "You've been gone for months! Long absent, soon forgotten."
Cliché gone or dead and still remembered. The good days we used to have together are gone, but not forgotten.Uncle Harry is gone but not forgotten. The stain where he spilled the wine is still visible in the parlor carpet.