All relationships have their ups and downs. What is important to remember is that empathy for the other is what keeps communication alive and solves problems, whatever they may be. Otherwise, you and your partner will create scars that will remain there for the duration of your relationship.
Remember that words are heavy and hurt a lot, so think twice before you speak and be tactful. There are some things, for example, that you should never say to your spouse.
Never threaten separation/divorce
Never tell your partner you're leaving if you're not serious. The fear of abandonment is deeply rooted in each of us and when you put this kind of pressure on them they feel badly threatened. The inner dialogue confronts the idea that it is actually possible to live without your partner. This type of "threat" causes mistrust and feelings of rejection that consequently affect the creation of distance in intimacy.
Never use the phrase "don't start"
It is very insulting and humiliating for the other party. These words show the dominance that the partner has over you and the lack of desire to listen to your argument or criticism.
Never say "you're like your mother"
Or as any other family member. It makes them feel hopeless and above all creates unnecessary animosities. Respect everyone's limits and again, don't forget to be empathetic.
Don't say "I don't respect you anymore"
This sentence puts a stamp on every conversation and is very heavy for the other. You feel weak, mistreated and unappreciated by the person who is supposed to support you the most.
Don't say "do as I say"
You make him feel inferior and your relationship seem suffocating.
Don't say "you always do that..."
It is a type of toxic language that makes the partner defensive and this creates distance.
As you can see, the key is in the communication you use.