Even if you're both ordinarily easygoing people, you'll get under each other's skin and become a lot more irritable through the course of this relationship. Perhaps in the beginning you'll start out arguing only about the important issues that come up between you, but the way you'll argue will really be hurtful to both of you, not to mention destructive to the relationship itself. And over time, you're likely to begin arguing over just about anything, as your levels of sensitivity toward each other rise and you both try harder to get in little verbal jabs during your arguments, to hurt the other person in the way that you've been hurt.
Needless to say, this isn't a good way to foster intimacy and warmth between you; in fact, it's a much better way to head toward a breakup. But you don't have to conduct yourselves this way, especially if there are lots of other positive aspects between you to outweigh this one. You could both learn to watch the way you speak to each other during an argument, and try your hardest not to be derisive or belittling of one another; you could also try taking breaks away from each other while you get your thoughts and feelings sorted out. But if there are lots of other indications of conflict in this relationship, it may not be worth trying to salvage.