I and people like me often think of the work we put in on a relationship as accumulating, building up a bank of good will that we can then draw from when we make mistakes. We imagine :
State += (deeds).
In reality, it's more like
State = (deeds)
State -= time decay
State :-> (deeds)
Where I just made up the :-> which means "drive to" in the sense of my cubic controller ; a variable is "driven" towards a target, via lerp or PD controller or cubic or whatever.
That is, doing good deeds (buying flowers, giving massages, being patient, going to the ballet) doesn't build anything. It just sets the current level, and you have to keep doing it all the time.
When I'm a fucker, I often think "I've done all these good deeds, I've proved that I love you and will stay with you, you should cut me some slack" ; I imagine that the bad deed is just like "State --" , it just takes off some of the credit that I've accumulated. In reality that's not true, again it's just more like an assignment
State = (fucker)
State :-> (fucker)
In a game theory sense, we can think about how to use this. If you only have limitted budget of good deeds, when should you do them? The most important time to do them is right after you're a fucker. You certainly shouldn't do a bunch of them all at once, because they don't add up credits that you get to keep. If you've done really good, you should just coast on that for a while as the state bleeds down before you do something to replenish it. (actually it's even more extreme than that, because of relativism and baseline recalibration, doing lots of good deeds in a row can doom you, because anything you do after that will seem worse than "the good time").
One thing I struggle with is the sort of Buddhist idea of detachment. The Buddhist idea is that you shouldn't be affected by your environment; that is, your happiness should be inside your own head; you should observe and be involved in your environment, but it shouldn't pierce your inner bubble of self. This has always not made sense to me. If I'm supposed to be unaffected by the negative things people say to me or what I see, then I should also be unaffected by the positive things, right? So I should take no happiness when someone says they love me or when Richard Feynman tells me I'm the best physicist he ever met? That doesn't make any sense to me, what happiness am I supposed to take? And if I take happiness from those things, then logically I must also take sadness from the opposite.
Anyway, you do need this detachment to some extent in relationships. Your lover will inevitably have moments of bad mood or anger at you or insecurity or whatever, and they will act like a real motherfucker to you and say horrible things. You can't be too affected by it when they do that, you have to know they don't really mean it. The problem is when they do that, you don't yet know it's just a mood. The way you find out they're in a state is because they said X to you, so at the time when you first hear X, you don't yet know they're in a state. That means you need to be able to hear them say X and not react too much. You need a detachment that lets you sort of ignore them when they say something bad or weird.
This is a weird thing I haven't quite figured out, but I think I'm getting better.