Liz, what things have changed recently that she might literally be pissed (USA meaning) about? Maybe try putting a catbox where she pees OR put her food there? If you can catch her while she's doing it, pick her up like her mother would, by the nape of the neck, and scold her, putting her in the catbox? You could also get some of those incontinence pads and out one down where she goes; at least it would make clean-up easy.