The New York Times recently ran an interesting article headlined The Happy Marriage Is the ‘Me’ Marriage.
Tara Parker-Pope wrote about not what makes a marriage last but what makes it meaningful, including the ways your partner makes your life better:

Dr. Aron and Gary W. Lewandowski Jr., a professor at Monmouth University in New Jersey, have studied how individuals use a relationship to accumulate knowledge and experiences, a process called “self-expansion.” Research shows that the more self-expansion people experience from their partner, the more committed and satisfied they are in the relationship.
To measure this, Dr. Lewandowski developed a series of questions for couples: How much has being with your partner resulted in your learning new things? How much has knowing your partner made you a better person? (Take the full quiz measuring self-expansion.)
“If you’re seeking self-growth and obtain it from your partner, then that puts your partner in a pretty important position,” he explains. “And being able to help your partner’s self-expansion would be pretty pleasing to yourself.”

Read the full article here.
This notion of self expansion being correlated to relationship satisfaction makes so much sense to me. A good mate should help you be a better version of yourself,  including experiencing things you might not otherwise.
Maintaining a healthy marriage takes work, and we want some payoff for that effort. Having a partner who makes your life richer than it would be if you’re alone seems like the return on the investment of your effort.
What do you think makes marriage meaningful?