You still have a ways to go in your career or your work for the public, and you learn a lot from this person, just by watching how they operate in their daily life. You have a lot to learn from them in terms of their general approach to life: how they treat other people, how they present themselves in public and so on. In some ways, this relationship is not just a romance, but a lesson in business etiquette and the keys to success.
This can happen in a number of ways. For example, if you're used to working long, hard hours and not leaving much time for fun or nurturing personal connections, this person teaches you to relax and to make that connection with your colleagues or employees. And similarly but conversely, if you've been somewhat undirected or lackadaisical about pursuing your career, this person teaches you about dedication and hard work, about the value of presenting a seamless, efficient and stylish face to the world, about networking and other ways to increase your professional stock value. Obviously, this aspect doesn't promote any romantic feeling between you, unless it's based in a sense of professional awe; you have to rely on other aspects between you to provide the personal intimacy that you crave as lovers. This one is strictly business.