It doesn't take much to realize that your energies are mismatched. There just isn't much intersection in the basic ways that you each meet life; your partner is more careful, conservative and pessimistic than you are (though they think they're being realistic!), while you're more impulsive and into taking risks. You often adopt a devil-may-care, rebellious attitude that makes your partner feel uncomfortable.
Because you're so different in your approaches to almost anything that comes up, you find that when you're together, upsets and obstacles occur with regularity. You make plans for the weekend, say, but then traffic slows you down, you'd take a detour and get lost, and then your plans would go down the proverbial tubes! This kind of thing happens again and again, and will continue to, until you can recognize that your ill-matched energies are actually creating obstacles. Before you're able to make that realization, you just get annoyed by the slow progress you make as a couple. Issues crop up -- you accidentally offend each other, for example, or challenge each other's sense of duty -- and you respond with irritation, blaming each other even for factors which neither of you can control. Unless you can face the fact that this frustrating energy is actually a product of the two of you together, it'll keep causing you trouble. Compromise helps a lot, as does resisting the urge to point the finger at each other.