Wondering what your marriage will be like in 10, 20, or 30 years? Things are looking good! The longer you're married, the more satisfied you are with your marriage, says author Maggie Scarf, who interviewed couples ages 50 to 75 for her book September Songs.

"In this new phase of life, couples don't feel the pressures of children and careers. They have time to reconnect," says Scarf, who first spoke to couples in their 30s and 40s and then revisited some of them decades later. "Those with troubled relationships now described their marriages as more rewarding than ever," she says. Here, three stay-happy tips:

1. Don't take things personally.
Jackie and Steve Winston used to fight about Jackie's perfectionism, Scarf says. Jackie had high standards, and Steve took her criticisms as assaults. But experience taught him not to take her perfectionism to heart. "I've become more capable of understanding Jackie," Steve says. "I don't take her words as an insult. I learned that her perfectionism is a part of her, not an attack on me."

2. Have fun together.
Couples in their later years have more time to try new activities and hobbies and explore new places — all of which can keep a relationship fresh. "These couples travel together, take courses, and go camping," Scarf says. "One husband prided himself on finding the best restaurants. Now is their time to explore parts of themselves that they never had a chance to focus on."

3. Be willing to negotiate expectations.
When Ned and Jean Donaldson moved to New Hampshire, Ned couldn't find work in his field, so Jean became the family breadwinner. "It was a hard transition," Scarf says. "But the two learned to enjoy the fluidity of their roles." Ned became the homemaker — he cooked and cleaned — and Jean enjoyed contributing in a new way. "I feel a sense of empowerment," she says. "The separate strands between us have woven together in terms of what we do."

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