At a UX conference not so long ago, a fellow presenter (a non-designer) and friend remarked that in so many of the presentations, he detected a tones of exasperation, almost whining, coming from the speakers. He wondered why so many designers were concerned with not being in a strategic or decision-making position, when the opportunity is theirs for the taking. I've encountered this quite a bit, and confess to being that designer in the past. At a lot of companies, especially larger ones, the goals and language set are dominated by people with backgrounds in business, sales and marketing. Much of what is discussed has an aura of rationality, science or math, its largely subjective, and its difficult for many designers to overcome the wall of jargon they encounter. Designers definitely need to learn some of this to approach the table, but they should be prepared to bring their own. Look for ways to shift the culture, ways to open up the discussion to include stories from real users, and ways to build on what's already being done.
Take a hard look at where you are working - is it even possible to achieve this? In my experience, if there isn't someone a couple rungs above you who gets it, you are in for a long, frustrating and probably futile quest. If this isn't working, find another company that does get it, work in consulting, or start your own. Agency work is appealing to designers partly because someone else is paid to inject them into the position they covet, but also because someone is running interference for them. They get to focus on design work while someone deals with the challenging clients.
I vastly prefer working in-house, where I see a rich range of problems and get the chance to see solutions through to conclusion and revision. It's a personal preference, and one that requires patience and stamina in different ways than other contexts.