By Allison Linn, CNBC
Forget that old adage, first comes love, then comes marriage. These days, it's more like, first comes college, a good job, maybe a house and a savings account – and then we can talk about marriage.
As a battle rages over the rights of gay and lesbian couples to get married, experts say the share of heterosexual Americans who are married has fallen dramatically compared to decades past. What’s more, the demographics of who is walking down the aisle also have shifted substantially.
In recent years, people with a college degree have become more likely to get - and stay - married than their less educated counterparts, and those who stay married also tend to be much wealthier than unmarried adults.
"Some people have talked about marriage as a luxury good," said Susan Brown, a sociology professor at Bowling Green State University and co-director of the National Center for Family and Marriage Research.
