The Four Horsemen of the Apocalypse is a metaphor depicting the end of times in the New Testament. They describe conquest, war, hunger, and death respectively. This metaphor is used to describe communication styles that, according to Doctor John Gottman, can predict the end of a relationship.
Here are the four horsemen.
Criticism is different than offering a critique or voicing a complaint. The latter two are about specific issues, whereas the former is an ad hominem attack. It is an attack on your partner at the core of their character. In effect, you are dismantling their whole being when you criticize.
Contempt is truly mean— it is when we treat others with disrespect, mock them with sarcasm, ridicule, call them names, and mimic or use body language such as eye-rolling or scoffing. The target of contempt is made to feel despised and worthless.
Defensiveness is typically a response to criticism. We’ve all been defensive, and this horseman is nearly omnipresent when relationships are on the rocks. When we feel unjustly accused, we fish for excuses and play the innocent victim so that our partner will back off.
The fourth horseman is stonewalling, which is usually a response to contempt. Stonewalling occurs when the listener withdraws from the interaction, shuts down, and simply stops responding to their partner. Rather than confronting the issues with their partner, people who stonewall can make evasive maneuvers such as tuning out, turning away, acting busy, or engaging in obsessive or distracting behaviors.
I have been a student and fan of this research for many years. In time such behaviors will destroy intimacy, trust, love, and the relationship.
Here is an article that further delves into this subject. There are many many detailed articles on this subject on the web.
There is also hope if your partner is open to changing these patterns and behaviors. Here is an article on antidotes to the horsemen.