I would see if an OTC allergy pill might help. I take one about every couple days as I am allergic to my cats, have cheap quality wall-to-wall carpeting and don't dust or vacuum very often, among other things. I liked Alavert but it makes me sneeze (I think the artificial sugars) so now I have changed to Allegra but I have tried a couple of the others; start with children's strength, see if it helps you?

I would talk to the woman yourself, not in any demanding or disrespectful way but just let her know you have a reaction to her perfume. She obviously does not know and might be happy to wear a different scent that does not bother you or less, etc. Where I worked we had a woman who got massive migraines from strong odors (she was the bookkeeper and personnel lady too :-) and new employees were automatically asked not to wear a lot of perfume or strong-smelling body lotions, etc.