The Karate Kid, eh. You were either a Boy, a Lad, or a Kid.

If I had to guess, I'd say the traitor was the Nemesis Kid, since the name seems to suggest opposition. (Googled: yes)

Wondering how this all worked out?

Projectra (often called by her nickname "Jeckie" a shortened form of her name) is a member of the royal family of the low-tech planet Orando, and possesses the superhuman ability to generate illusions affecting all five senses. During her membership in the LSH, she met, fell in love with, and married the martial artist Karate Kid. After her father King Voxv died, she fought both her cousin Pharoxx and her grandmother and mentor Hagga, who sought to usurp the throne. Afterward she became Queen Projectra of Orando, and she and Karate Kid became reserve members of the Legion of Super-Heroes. When the Legion of Super-Villains invaded Orando, Nemesis Kid defeated Karate Kid in personal combat and killed him. Projectra subsequently killed Nemesis Kid in revenge, claiming royal privilege to do so even though it violated the Legion's code against killing.