"Even after all this time the sun never says to the Earth, 'You owe me.' Look what happens with a love like that, it light the whole sky."
I found this quote such a beautiful analogy to how we should treat our relationships and what we do for people we care about. It isn't about keeping score. It's about doing things out of love and generosity without expecting anything in return. When we start to keep score with people, with things like; I paid for dinner the last few times, or I cleaned the house the last 2 weeks, we start to resent that other person. The only thing that comes out of resentment is negative energy and bad feelings towards that person, and they can sense it. It isn't healthy for a relationship. So don't keep score in your relationships. Do things because you want to, and don't expect the other person to always do something in return.
On the other hand, if you find that you are always the one giving and giving and the other person doesn't put any effort in, then maybe it's time to take a step back from that relationship. Most people who care will try to contribute in their own way, but just remember to not keep score and it will benefit all your relationships.