You two have come together for a bigger purpose, a spiritual ideal -- which, granted, isn't the most romantic thing two lovers can do together! But you focus together willingly on ascending to greater spiritual heights. If you tend to be a cynical, pessimistic type (though you might call yourself realistic!), this relationship can help you open up your soul a little bit and soften that hardened shell you've developed as a response to what can seem like an unstable world.
After all, your cynicism is just a defense mechanism you've developed as a response to various experiences that life has served up for you; it's not necessarily an accurate representation of the way the world really works. This relationship helps to open you back up to the intangible side of life, the mystical, ethereal, lyrical pleasures of love and human possibility. Your lover helps you to believe in magic, and you, in return, help them to stay grounded in reality. You might simply enrich each other's lives with your complementary perspectives, but you might also get into something more specific and directed in terms of spirituality -- going to church together or reading books about Zen Buddhism, for example. Even just gardening together can help to raise your sense of the mystery and magic of life while keeping your feet literally on the ground!