The level of unpredictability that exists between you doesn't bode well for the future of your relationship, unless there are plenty of other more grounding influences that can help to stabilize your connection. After all, a certain level of spontaneity can be fun, even exhilarating, but between you two it's likely to go overboard and verge into the realm of irritation. Your lover just doesn't ever feel as if they can depend on you, or know where the relationship is going.
If they have a taste for the unknown, this could hold their interest for a while. They inevitably want more stability and commitment than you do, and your relationship becomes a sort of emotional push-pull between dependence and independence. This could be leading to arguments, or it could just lead to a subtle feeling of neither of you ever quite getting what you want. This issue grows over time. Your partner wants emotional security, but the best they're likely to get is moments of intimacy that are interspersed with periods of aloneness -- during which they might not even talk to you much or know where you are! Needless to say, this kind of relationship doesn't foster the closest, coziest feeling in the world. It's up to them to decide whether they let this be a deal-breaker of an issue or whether they find a way to loosen their hold, relinquish their expectations and enjoy the moments of closeness that they find with you.