Matthew,
I have found that I am extremely hard on my brushes.
The Trekell Hog Bristle's spread out really quick for me.
I wear my sables down to a stub and I can actually hurt a Ruby Satin synthetic too.
My favorites are the Winsor & Newton Monarch Mongoose, here is a link:
Monarch Mongoose
These are synthetic too, and tend to be a little softer than the ones mentioned above, but they really hold there shape the best for me.
See you are not alone - I have actually used a pair of hair stylist scissors to trim brushes back to shape.
I know there are tons of suggestions on the care of brushes here. One piece of advise I can give you - if you are mixing the color you need with your brush vs a knife, this can really do them in. Get a good, to a point shape palette knife for this, your brushes will love you.