complusive hoarding

hi,
my mother is a compulsive hoarder, our house is a filthy s**thole as a result of this, she is now hoarding cats, so it is a stinking s**thole. For other reasons we must sell our house and I can't wrest the stuff away from her. even discussing the situation makes her angry and then tearful. by the time it gets hot, the house will stink too much to be able to show it anymore till fall, and by fall the softening market will probably steal fifty thousand dollars from the price we might be able to get right now. I am at my wit's end. it is a twelve room house so you can imagine the magnitude. even when discarding my own things i have to take them down at night before the trash collection or she will go through my trash and take in old stuff and hoard that too.
there are entire rooms where you can't even cross the threshold, and others where there is a mere path in and out.
denial is total. i am ready to walk away from it but it is my house too and my total assets are in that house.
any advice?