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.