As you know- spoilers are inevitable on a wiki page.
Before he "died", Bradley Baker was engaged to LB. In Pick your Poison, Ruby Redfort writes in her notebook that LB killed Bradley Baker, which she admitted when Ruby asked about it in the final book. However, she only shot Bradley's plane because Buzz (Casey Morgan) forced her to. She had the choice to either kill over 2000 people by a bomb or kill Bradley Baker. Everyone thought that Bradley was dead but he did not die, he was found by Lenny Rivers, affected with amnesia and was assumed to have the name, Morgan Loveday.
Ruby discovered that he was Bradly Baker in the final book. He is reunited with LB in the morning star coffee shop. He gradually has his memory restored and remembers LB. Unfortunately after this discovery he soon dies in combat leaving LB 'full of sorrow' but grateful to Ruby for bringing Baker back to her.