Rav Shlomo Wolbe zt"l was one of the great baalei mussar, Jewish ethicists, of the latter half of the 20th century. The following piece shares one of his important insights into marriage:
The parsha begins with Avraham inviting three angels guised as Arabs into his house and offering them a royal feast. The Torah describes the encounter in great detail thereby revealing an entire handbook for the proper performance of chessed. While most of the narrative focuses on the way a host should treat a guest, the story ends with the chessed a guest should perform with his host.
After the angels finished their meal, they asked Avraham where Sarah was, and he responded that she can be found inside the tent. Rashi explains that the angels certainly knew where Sarah was. The intent of their query was merely to endear Sarah to Avraham. Their question would prompt his answer, "She is in the tent," thusly highlighting her middah of modesty. Avraham's articulation of Sarah's qualities would bring him an added level of appreciation for his wife.
Rav Wolbe comments that it is amazing to think that there was a necessity to endear Sarah to Avraham. Chazal tell us that when Avraham married Sarah he was twenty five years old. When the angels paid their visit he was ninety nine - nearly seventy five years after their wedding. Endearing one's wife upon her husband would seem to be something necessary for a couple who were just married as opposed to a couple many years past their golden anniversary! Nevertheless, the Torah tells us that an essential aspect of marriage is ensuring that the husband and wife appreciate each another.
Interestingly enough, writes Rav Wolbe, the closer the relationship between two people, the more difficult it is to show and voice appreciation for each other. The pair becomes so used to each other's contributions toward their relationship, that they begin thinking that the other party is indeed obligated to contribute all that he does. Thus, he is blamed if he fails to provide these services. This puts a damper on their relationship.
This is an idea which is particularly important in marriage. The house is a place of mutual chessed. Whether the husband works or learns, he spends his days toiling to bring material or spiritual sustenance into the house. The wife spends her days taking care of the house and looking after their children. Each of them must constantly find ways to show their appreciation of their spouse for all that they do. Focusing on the many things the spouse does, as opposed to focusing on the few things that they do not do, brings one to appreciate the numerous qualities of their spouse and the many contributions that they make. If the angels felt it necessary to endear Sarah to the elderly and holy Avraham, we can be certain that acknowledgment and appreciation of a spouse's qualities is imperative to a good marriage no matter how long one is married!