It is difficult for most people to move from reporting again and again (rehashing) the problems in their relationship. The problem leads to hurt and mistrust so it continues a cycle of emotional pain. I believe this comes from a point of fear of being hurt. "I will never let that happen again", so we keep playing the bad feeling or problem over and over to guard against the painful incident reoccurring, now you are really stuck in the problem. Communication is now set up to be defensive and negative.
Couples don't take time to think of their options to the problem. To stop and ask yourself "why am I reacting this way," is difficult at first and takes practice. Most couples just continue to react to what their partner is saying and doing, and do not stop to ask the question what is the best way for me to respond? Once you see you are in the loop of negative communication you can slow down and say something different. 1) let me think about this a minute 2) I have a concern this is going in a bad direction, or 3) let's take a ten minute break and come back. There are ways to get to a more focused outcome, you have to decide you don't want to keep repeating the negative communication loop.
There are ways to move from the problem to the solution. If you have the commitment to the relationship and willingness to make changes, you are well on your way to less rehashing and toward productive solutions.