I heard one man say it was having seperate tv sets

Dunno, but I'm very glad to be in one (I think (so far so good))!!

Things that might help
(1) similar approach to money: spending, saving, vacations, possessions, etc.
(2) Kids and a similar approach to child raising.
(3) Get along with each other's families.
(4) Willingness to give each other space at times.

My wife & I also have a fair amount of overlap in the books & movies we like. Not 100% by any means, but there are plenty of things we can enjoy together.

My father, now passed; kept his vows for 31 years.

My mom plans to keep hers till they meet again someday.

Short lives.

Respect and not taking much for granted. Looking at it as a partnership with a roommate, complementing and helping each other, rather than ownership.

Ehhh... Idk, maybe the fact that I'm so glad when he's at work all day!

Determination

Hard work at it 100% on a daily basis!

Love, respect and remembering that your partner is a person in their own right.

Empathy and compromise... With a big dash of love

Mutual love, trust, forgiveness, patience, shared values

Polyandry

Faith and fate.

I don't know. I never got to that either time.

I honestly don't know anymore...

Truth and trust but dont expect that anymore

hard work diplomacy, and patience

Early unexpected death?

In-law shotguns?

Heck if I know I am on my second divorce!!

An early death

High tolerance or love

Lack of divorce, mostly

1/3 ration and a beating a day!

A shotgun! BOOM!

Both people have to work at it.

Butt secks? It's spiritual!

Death.

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