I also have sensitivity to smells - Big time. It really hinders my life I hate soap powder on clothes , shampoo on hair, coffee or mint on peoples breath.
I try to keep my house free of smells using Ecover products to wash my clothes, fragrance free soaps and bicarbonate of soda to clean everything else in my house, this helps reduce sensitivity and keeps me happy in my house.
When you are in others company it is more difficult, i try to avoid situations where I will be in close contact with people, don't like this anyway.
The only other tip I can offer is to breath shallowly, don't take deep breaths, try to distract yourself, keep a window open.