Patty Wells was the girlfriend of Tom Griffin before he met Linda.
She got her first and only mention in "The Daria Database", where we learn Tom keeps thinking if he should have married "plain Patty Wells" instead of Linda. "She was always so happy to see me and such a good sport. Still, there was that mole..." Needless to say, she's better off.
She appears in Charles RB's "That 70s Fanfic", where she's a roommate of Jordana and lives in the same apartment as the Morgendorffers. Here, she was engaged to Tom when he left her.