Instability--Linda could relate, really, except in a less literal sense.
The angel thing Linda was always glad to tell anyone--how a screw-up like her had her life saved and how she became Supergirl. It gave people hope.
"Well, it's a really weird story," even Linda had to admit, "I was a pretty awful teen who had a literally demonic boyfriend that tricked me into joining a cult and I was saved by the previous Supergirl, Mae--did Ma and Pa ever tell you about Mae?"