The old Woman was one of three elders that Janeway met when she began a Nechani ritual to purify her from an energy field that had struck Kes down. Janeway was trying to discover the secret of the energy field so the Doctor could help Kes recover. The old woman told Janeway that she was also waiting for the ritual to start and have been there for as long as she could remember.
After Janeway goes through the ritual, Kes' condition does not improve. When Janeway retuns to the planet she meets the three old people, who are really Council Members. They chide Janeway for having no faith, and for using technology to try and cure Kes. Janeway with new found faith, carries Kes into the shine, and the energy field does not harm them, and Kes recovers.