In each other you find a lover who encourages you and understands you, and helps you find your way. Your partner feels as if you're their safe harbor, the person they can come to for inspiration and guidance in life. Your natural spontaneity and enthusiasm is a support to them, and they come to you for advice because they know that you understand them so well.
They need to establish a direction for themselves, for their future, and you help them do that -- and in helping them, you define your own life path more closely. But this isn't (and shouldn't) be based on an idea that you know what's what, and where your partner ought to go in their life; it is much wiser to take the perspective of not knowing, and simply following the signposts as they appear. Staying open to opportunities is a big part of this influence, and whenever you two can do that together, some amazing things will result. As long as you're communicating clearly and not trying too hard to guide each other in a forceful or manipulative way, you're a real help to each other.