Bye Bye Love

The Name of the quest might be a reference to the "Everly Brothers" song of the same name.

Currently, due to a glitch, Carlitos isn't appearing in the game for many people, making the quest temporarily unfinishable.

-- SPOILER --

To fix this glitch simply go to the dinner in the Vault 21 hotel and type player.placeleveledactoratme 11f862 into the console. This will spawn Carlitos right in front of you.