“The dogs bark, but the caravan moves on" (Arabic Proverb). "Things cannot always go your way. Learn to accept in silence the minor aggravations, cultivate the gift of taciturnity and consume your own smoke with an extra draught of hard work, so that those about you may not be annoyed with the dust and soot of your complaints" (William Osler).
It's a long step from complainant to complaisance. The physician Dr. Edward Trudeau had tuberculosis and his approach was, "I have found that the great word is Acquiescence." Sophisticated folks have a hard time acquiescing to anything, much less everything.
Disraeli, when Prime Minister of England, was known to have an excellent memory. Someone asked him one day how he managed to remember all those names and faces. "When I meet a man whose name I cannot remember, I give myself two minutes; then if it is a hopeless case, I always say: `And how is the old complaint'?" And asking some people, "How are you?" can ruin our day. Disraeli is also quoted as having said, "Never complain and never explain." Self-justification fans just as many fires as criticisms and grievances.
A strap hanger is one who has a complaint of long-standing. The word strap has many definitions. Among many meanings, the noun means belt and the verb means beat. So we can wind up belting ourselves and beating others with complaints. If the complaint is long-standing, we then shoulder the heavy epithet of strap hanger. Proverbs 25:17 wisely teaches, "Seldom set foot in your neighbor's house--too much of you, and he will hate you." This is especially true if we go there with nothing but grievances. We'd best get a grip on our gripes!