You stimulate the most idealistic parts of your lover's nature, which sounds nice -- except that you could encourage them to step off the edge of the mundane world and into the stratosphere with you. While this is fun and pleasurable, and makes you feel closely bonded as a couple, it does present some problems. Your lover is so idealistic when they're with you that they could become quite irresponsible.
After all, if all their focus and interest goes toward the uplifting feeling of being together, they don't get much done in the way of tedious, day-to-day responsibilities. They tend to be indulgent and enthusiastic, while you're rather gullible and impressionable, and that can be a bad combination. You mislead your partner -- unintentionally, of course -- and could actually deceive them about good risks or investments. You talk each other up and it could be hard to come down again and face reality when it intrudes, which it has a nasty habit of doing. Over time, you might even start to realize that you've overlooked the fact that you're not all that spiritually or philosophically attuned; all this time, you've been convincing each other to get involved with ideas or activities that don't even match up with your true values. This confusing effect has to be faced and dealt with; otherwise you just mislead each other without even meaning to.