If I were you, i'd look at what my triggers were and find some beer styles to enjoy that don't factor into the triggers. I've always heard that sulfurous compounds can trigger bad headaches in wine drinkers, and that might also factor into whiskey drinkers if they're aged in charcoal lined oak wine barrels. That being said, i'd probably skip any beers aged on oak for any length of time. A lot of whiskey stouts and Scotch ales are oak aged in this way.
Since you believe that your triggers are related to the bittering compounds from hops, I would use ratebeer or beeradvocate to check the IBU's of the beers you're planning to sample. The BJCP style range for homebrewing can also give you a guideline for how hoppy a beer style should be (in a range) in IBU's (International Bittering Units). The higher the IBU's, the more bitter they taste.
Pick some styles that are low in IBU's and give them a taste test. Many session beers (low gravity mass market beers) are going to be low in IBU's, such as: Pale ales, pilsners, cream ales, fruit lambics, porters, belgian golden ales, etc..