This is a long shot but simply food for thought:

If it is common knowledge that you are bipolar, she could be considered harassing or discriminating against you due to your disability. It would take proving that she is treating you in a harmful way because she knows of your disability and doesn't like being next to you. You might confer with HR about it. Also, she must be treating you in a different manner than she treats others currently sitting near her. JMHO HR would be able to help you on this one. They are also responsible for helping you with any accommodations that will make doing your job easier, i.e. changing desks.

Hope things get better for you soon. Hugs.