To be honest, it's not as simple as this is the problem so this is the solution.
I do want to give you an answer though so I'm hoping an example will do.
A client came to me and said that she feels like every time they talk, they end up arguing. This is something I hear a lot.
When I asked some questions, what's happening is that when they argue, they can both be quite mean with their words. When she approaches him she feels nervous and with the expectation that it will probably turn into an argument. She starts the conversation expecting it to go wrong and so when it does it compounds the anxiety for the next time.
I ask her questions about why she wants to discuss it with him, what is she hoping to gain. Not what does she expect to happen, what would she like.
She just wants to have a conversation, the topic is an excuse for communication, it's a reason to say something in a relationship that has otherwise become quiet. So I helped her to work on feeling more secure in herself so she can not be as anxious, also to remember the ways in which her husband can help and comfort her, even if he hasn't been that person in a while. She approached him differently, was more hopeful and didn't expect an argument because she went into the conversation already deciding that she wouldn't engage in an argument. So once the anxiousness of a doom cycle (as she called it) wasn't there, they were able to talk. Not for very long initially, but it opened the door to longer conversations that then felt less tense and easier as they went.