

The best thing you can do is treat her respectfully. Say hello when you pass and be courteous when you talk, but putting up the professional barrier to any kind of personal relationship likely is your best strategy.
Your coworkers also see these traits. They will see you treating this person with respect, but also not participating in her drama. That’s the mentality you should have to forming a winning workplace presence. People will see you treat her kindly, but also do not participate in the drama.
Everyone respects that person
The taxes get made up on the back end.
Bonus money is taxed at the rate that applies if that was your regular salary. In other words
If you make $1,000 a week that’s equivalent to $52,000/year salary. And it’s taxed at that rate.
If your bonus works out to a $2,000 a week rate that is taxed as if you make $104,000/year.
However, once it is time to actually do your taxes the IRS will see you made $52,000 in salary and $2,000 in bonus. So your actual taxes owed will be on $54,000.
So whatever extra taxes you paid at bonus time get returned when you do your taxes.
I used to work entirely on commission, and occasionally I’d have such a good week I’d hit a ridiculous tax bracket. Most weeks were ass though, so tax season was always great because I’d get that money back