There is a disconnect between your partner's daily experiences and your moods and emotions. Somehow, you are out of sync; your lover may have a fantastic day, full of good things happening, and they'll come home to find that you're feeling gloomy and pessimistic -- and they'll be dragged down. Or, on the opposite side, you could have an awful day and feel annoyed by your partner's unfailing good humor, and consciously or unconsciously, you do all you can to pull them down to your level.
As your relationship progresses, you may find that something in your individual daily routine is in direct conflict with that of your partner. You could be living more in the past than your lover, held sway by some old experiences or hurts that have never really gone away. Your partner lives more in the present, and they have the chance to teach you their way of living -- letting go of the past and moving forward. Obviously, this is an important lesson to learn, but a difficult one. When any of us encounters things in our present life that remind us unpleasantly of our past, our instinct is to rebel against it or run away from it, unless we've already done the hard work of processing the past. That is what this relationship is about, in part, for you -- facing your past and learning to live in the here and now.