When the Central Power Battery on Oa was destroyed, the power rings of Green Lanterns across the universe disintegrated. One such Green Lantern was Adara. She had been a Green Lantern for years, protecting her sector. Her power ring disintegrated during a fight with Corellian privateers. She would have been killed, except the privateers captured her. She later managed to escape.
[Green Lantern Vol. 3 #50, #56]
Adara met Kyle Rayner in an alien cantina, where he had been involved in a bar fight. She was surprised to see a Green Lantern with a working power ring. Being a Green Lantern was the only thing that mattered to Adara.
She stole Kyle’s ring in an attempted to be a Green Lantern again. The ring would not work, and Adara was almost killed trying to be a Green Lantern.
A modification of the standard power ring the corps used to have, Kyle’s ring couldn’t be used by anyone else except for him. Emotionally overwhelmed by the realization she would never again be a Green Lantern, Adara committed suicide.
[Green Lantern Vol. 3 #56]
Adara is memorialized in the Crypts of the Green Lantern Corps on Oa.
[Green Lantern/Sinestro Corps: Secret Files #1]