Unexpected Habits That Can Sink a Marriage

You Light Up Alone

He kicked the cigarette habit, but you can’t. It’s a vicious cycle: You smoke, he complains, you fight, you stress, and then you need to smoke again. (Although correlation isn’t causation; there are other risk factors too.) A group at the Centre for Economic Policy Research in Australia found that smoking was not a very high risk factor in a marriage if both couples are smokers. But divorce rates increase significantly—76-95 percent higher—when only one spouse (especially the wife) has the habit. Quitting saves your (love) life.

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