Question about bedding

Louise, my old lady pig, has decided that it is perfectly alright to pee her bed and lay around in it all day. This has resulted in her saturating her hind end to the point where the fur is totally discolored and she really is quite stinky. I've had to give her 3 baths in the past week (I tried plain water rinsing, but the urine smell was still very strong). Mind you, in her entire life I think I've only bathed her a half dozen times, so I really am not keen about so many baths.

Right now, her cage is bedded with kiln dried pine, which is what I've always used. I clean out the bed area every day, and even twice a day now, but she soaks herself almost immediately. She also has a fleece cozy that she sleeps in, and the same thing goes there...within a few hours, the bed and Louise are soaked.

I know she's not incontinent, because I can hold her for 45 min. at a time and she doesn't pee at all. She's also quite mobil, still using her ramp and puttering around on floor time (where she does fine with her potty pan).

Would some other bedding be better for her sleep areas? I know alot of people use fleece, but when I tried pouring some water on the fleece I have, it just pooled, so I don't see how that would help, since she would just be sitting in the pool.

I don't want to have to bathe her so often, but I don't want her to get ammonia burns on her bum, either. Any suggestions?