Toilets, Sinks, Showers, Tubs and Disposals - a crushed brass bonnet

I'm trying to replace my 3-handle bath faucet, and crushed a brass bonnet, because it was so tight and my socket just crushed it. Now I can't get it out, any idea on what I should do? thanks very much.

What is it exactly that you crushed? Is this a shower or a sink? Are you trying to replace a valve stem or the whole thing? What does crushed mean---rounded

Its shower, I'm trying to replace the stem, and yes it is rounded.
Thanks.

A little surprised noboby has weighed in on this. I mean plumbers must run into this now and then. I think I would do this. They[maybe sears] have locking pliers that have the threads running long ways on the jaws. inline with the handle. I would lock one of those suckers on tight as I couldand turn it with a big screwdriver,or whatever, through the handle. Try to stabilize the wrench at the end of the handle so it doesn't move sideways. I would first use a "penetrating lubricant" [not wd 40] and let it sit there over night. Put it on at dinner and again before bed. Try it it the morning. If you already got it out let's hear about it.