Good Luck. I wouldn't retaliate though or do something stupid, your reputation is pretty important. I'd agree with what a lot of people have said - document everything. Make a log, at the very least if you are ever called to defend yourself or to give an explanation for anything, you have everything there and you will know it off by heart. If it comes to it, you will be able to talk confidently around everything that has happened etc, whilst this nightmare co-worker will not, be caught out in lies.