Name it
The method is three things, and they happen in order. Name the row. Agree what it's about. Handle the next instance. The first two are done once, on a calm day, and the third is done every time. This chapter is the first.
Find it. Go back to your chapter 1 list, the five rows with their first and last sentences. The first sentences were five costumes. The last sentences were the row. Look at them and find the two worries from chapter 11, being blamed and being left to it. One of your last sentences is probably a left-to-it sentence, "I have to do everything", "it's always me". One is probably a blamed sentence, "nothing I do is right", "I can't win". Those two sentences are the one row. Everything above them was costume.
Name it. The name should be plain, short, and yours. It shouldn't be clever and it shouldn't be an accusation. "The on-my-own row" is a name. "The row about you never helping" isn't, because it's one side's underneath dressed as the title. Some couples name it after the first costume it ever wore, "the dishwasher", said with a slight smile, and that works if both of you can say it without an edge. What matters is that both of you would say "yes, that one" when you hear it. If one of you winces at the name, it's the wrong name.
Say which worry you carry. This is the part that takes some nerve. Each of you says, out loud, which of the two worries is yours in this row. "When it starts, what I feel is that I'm on my own with this." "When it starts, what I feel is that I'm being told I'm useless." You may find that you're both in the same worry, and that's fine, but chapter 12's guess is that you're in different ones, and that hearing your partner name theirs will be the first time you've heard the row from their side.
Do it on a calm day. Not during an instance and not the evening after one. A Sunday afternoon, a walk, a drive. Say beforehand that you'd like ten minutes to talk about the row you keep having, not the last instance of it, and that you're not going to raise the dishwasher. Keep to that. If the conversation starts sliding into an instance, one of you says "this is turning into the row" and you stop and try again another day. That isn't failure. It's the row showing you where its first step is.
Naming it isn't solving it. It's the difference between a thing that happens to you and a thing you can see. The next chapter is what you do with the view.