Small misunderstandings between you are common, and though they usually are not a huge deal in themselves, their cumulative effect could be adding up to a certain level of tension in your relationship. You just don't read each other right; you misread the cues that come your way and end up feeling unappreciated. If there are other challenging aspects between you, this one could make those even more troublesome.
Somehow, a pattern was established in the beginning of your relationship that causes you to hear each other wrong. Picture this: If you think your lover never says thanks for gifts or favors, you develop the perception that they take you for granted -- when, all along, they've been thanking you for what you bring to the table, and you just can't seem to hear it. So they're doing what they can to be grateful and appreciative, but you can't take in the gratitude, and you end up feeling unappreciated. This is just the kind of situation that happens between you two. What to do? You don't find much common ground to stand on, and whenever one of you makes a move to bridge the gap between you, the other misinterprets the move and the sentiment is lost. Any overall positive bond might just have to rely on other more beneficial aspects that exist between you.