The most beautiful flowers and gardens I've ever seen were in Washington state, honestly.
Don't take everything you read so literally! Books tell you ideal cultural information. Many, many, plants don't like wet feet in winter, but that doesn't mean it can't be done. Plant those plants on mounds. Amend with compost. Such plants might be shorter-lived for you than in drier climates, but that doesn't mean they can't be grown.
I'd be willing to bet that I get more rain, and certainly snow, than Seattle. My son, who grew up here, now lives in Seattle. He says people Seatte don't know what a storm is. You get mist, we get torrential downpours. You get dustings of snow- we measure it in feet. But I have clay soil, and I grow coneflowers, rudbeckias, salvias, lavenders.. I just adapt the plant's conditions a little.
Karen