You learn a lot from your relationship with each other, and not just about yourselves, love or the ways in which two people can connect and grow together. You learn all those things too, but you, especially, also get a wonderful and much-needed lesson in pursuing your career. Especially if your lover is further along in their career than you are, they're able to set a really good example for you in terms of networking, self-promotion or even just seizing opportunities as they come up.
Even if that's not the case -- even if you're both already established professionally, or if neither of you has actually started your career or even settled on one yet -- this person is still an inspiration in this area of your life. They're right there with you along your professional journey, cheering you on when you meet with successes and lending a shoulder or an ear when you need some comfort and commiseration. In fact, communication is a big strong point between you in terms of taking strides in your careers. Your lover helps you to brainstorm new tactics for advancing yourself, they offer you important advice that helps you to make better decisions in business, and they give you a lot of encouragement to get out there and make things happen.