Personally, I like the piece of driftwood you have; it is very interesting, visually speaking. However, if you are having problems with it breaking apart, then it obviously has a rotting issue, and you really don't want wood decomposing that much in your aquarium unless you have something in there that normally eats soft wood. You can usually salvage soft driftwood by scrubbing it with a wire brush until you get down to the solid wood. You can use a drill-mounted wire wheel–which will "eat up" the wood quickly, meaning it is easy to overdo it–or a mechanic's brush in either brass (more gentle) or steel (more harsh). You can usually pick up a set of those two plus a nylon brush fairly cheaply. If you're getting just one, go for the steel one. That's the one I use most unless I'm working on a more delicate piece of driftwood. And if you can salvage a cool looking piece of driftwood, then that's one piece you will have to work with in the future. Plus, you'll already have the tools to "dress" any wood you might find for free in the future.
Good luck with your rescape!
"May the Fish be with you."