My beloved friend and chavrusa, ohev Torah amiti and great baal middos, Bnan Shel Kdoshim, R' Mordechai Ziskind Hager Shlita, told me that he was chatting with a very prominent psychologist who charges $1000 a session for his services [great job for a kollel man. He works one afternoon a month and he is SET!! I envy his wife and children. When they sit and have a Shabbos meal with him, it is a $2,500 value]. R' Mordechai asked him what is the entire "Torah" on one leg. What makes a person successful in interpersonal relationships?
The psychologist answered [you may read and I won't charge you:-)]: One compliment a day.
R' Mordechai spoke at shaleshudes in the shul next to the Great Synagogue [in Heichal Shlomo] and mentioned this idea. Some time later an ooolllddd man in his eighties or even nineties approached him and told him that he has had a great relationship with his wife. He wishes his great shalom bayis on all yidden. But after he heard about the importance of giving a compliment he took it to heart and started doing it. He had been lax because he had taken much of what his wife did for him for granted. He said that since then things have improved considerably.
Try it......:-) It works on a roommate, a chavrusa, a neighbor, a Rav, a parent, etc. etc.