I'm with everyone else about just getting a new one, but if you want to get the old one off, here's how:
Chuck the shaft in your lathe with the ferrule about 1" out from the chuck. Make sure you support the back end of the shaft.
Spin your lathe in reverse rotation at a good fast speed, at least 800, but more is better.
Wrap a leather shaft burnisher or scrap around the ferrule and use a pair of pliers to put a little squeeze on it. You don't want much, all you're trying to do is generate enough heat to loosen the epoxy. As soon as it softens, the ferrule with unscrew and come right off.
I've done it dozens of times, but probably not in at least 10 years. It really does work well, just don't over do the heat and tear up the ferrule.