Based on a fundamental marital Shaloim Bayis letter https://kabbalahwisdom.org/marital-mediation-the-rebbe/ from the Rebbe, there are five fundamentals to Shaloim Bayis (which remarkably are not that well known)
1. “The central aspect in the manner of conducting a home and family life, is, that it be based on the way of the Torah, whose ways are “ways of pleasantness, and all of its paths are peace.” If this rule applies to all activities of a Jew, even outside the home, how much more so does it apply within the home itself.”
2. “Since G-d has created human beings with minds and feelings of their own, and these are not uniform in all people, peace and harmony can be achieved only on the basis of “give and take” that is, meeting each other half-way. For a husband and wife to make concessions to each other is not, and should not be considered a sacrifice, G-d forbid. On the contrary, this is what the Torah teaches and expects, for we are talking about concessions that do not involve compromise in regard to the fulfillment of Mitzvos, and both of you are of the same mind, that the laws of the Shulchan Aruch must not be compromised.
Furthermore, to achieve true peace and harmony calls for making such concessions willing and graciously –not grudgingly, as if it were a sacrifice, as mentioned above, but in the realization that it is for the benefit of one’s self and one’s partner in life, and for one’s self perhaps even more, since it is made in fulfillment of G-d’s will.
There are many sayings of our Sages, as well as those of our Rebbes, urging husband and wife always to discuss matters of mutual concern, and to give patient attention to the opinion of the other and then act in mutual agreement.”
3. “Our Sages exhort every Jew to receive every person with a friendly face, certainly it applies to one’s wife or husband.”
4. “It is also very desirable that they should have at least one regular study period in a section of Torah which is of interest to both, such as the weekly Torah portion, or a timely subject connected with a particular season or festival.”
5. “Finally I would like to add that of the Mitzvah campaigns which have been emphasized in recent years, special attention has been focused on the mitzvah of Ahavas Yisroel [the love for fellow man,] which embraces everyone, even a stranger; how much more so a near and dear one.”