If Condesce is the Alternian Meenah, then how did she keep Psionic alive? Meenah is the Theif of Life, and as we see with Vriska, the Theives take their aspect for their own. Is it that she took it from others and gave it to psionic? Or was there some other method?

Theives take and use their aspect for their own purposes, so she most likely took like from others and gave to the psioniic