After the events of Army Of Darkness, Ash gets his old job back at S-Mart, and meets Jenny (who works in the Arts & Crafts section, and she may have been the woman we see Ash kiss at the end of the film). A few years later, Ash starts having nightmares of the events that took place at the cabin. Though she doesn't believe him, she takes him to the Cabin so that he can confront his demons. Little does she know, her promise is all too real when Ash's severed hand plays Raymond Knowby's tape containing the passages of the Necronomicon.
The Kandarian Demon attacks her through a window and drags her away. Ash later finds finds her possessed, and attempts to exorcise the demons from her with Father Allard. During Father Allard's "revealment" she is exorcised, but is then kidnapped and taken back in time to Damascus.Eventually Ash defeats "Allard" and returns himself and Jenny home - only to discover that history has changed and the world is now ruled by the Dark Ones.
In Evil Dead: A Fistful of Boomstick it is said that she died in a bus crash. Presumably somehow she and Ash managed to get back to their own timeline before this happened.
Ash and Jenny were in a relationship.
In Army of Darkness it is revealed that Linda worked at S-Mart, so presumably they were aware of each other. Since Ash has been known to lapse into periods of grief over Linda's death, it's possible that she may harbour feelings of resentment towards Linda due to Linda being considered be "the one" by Ash, although nothing of this nature is ever mentioned, so it's more likely that she simply wants to help Ash get over her death and move on with his life.