It means: Although a long and intimate marriage is difficult, you can get some great things out of it.
monogamy
Monogamy means the practice of having only one wife
My aunt is monogamy.
The Myth of Monogamy was created in 2001.
Monogamy - album - was created in 2000.
serial monogamy
Synonym: Bigamy Antonym: Monogamy :D
monogamy
The Game of Monogamy was created on 2010-10-05.
monogamy
monogamously
Monogamy is legal in all 50 states. Maybe you're trying to ask about polygamy?