Getting along with each other is the tricky part of this relationship. You both try to express yourselves in the ways that you know how, but your ways are directly in conflict with your partner's. You take the well-thought-out, logical approach, while they shoot from the hip, so to speak, acting and reacting on gut instinct.
It's a case of calculation versus impulse, and you're both irritated by the other's way of thinking and communicating. Small irritations can turn into bigger misunderstandings, and then that impulsive reaction mode clicks into place -- and then your partner, especially, forgets to be tactful and kind in their rush to get at you. When feelings get hurt, it's natural to want to retaliate by striking back, but this is something that you two aren't able to stop doing! Even if you're ordinarily a placid person, in this partnership your temper is stirred up and you end up saying things you don't mean, hurtful things you wish you'd kept to yourself. Emotional situations, especially, may be ground for faulty reasoning. You both just start reacting instead of trying to assess the situation calmly. Needless to say, this kind of chaotic energy can wear down the best of romantic connections. It's hard to feel as if your lover is also your adversary, and that's the likelihood with this aspect. Trust and respect will slowly erode unless you can find a way to tone it down when you're together.