But therapists have found that couples who clearly express their appreciation and empathy for one another have longer lasting unions.
"If you and your partner regularly use these phrases, it's a sign that you're already a mentally strong couple," she says.
"And if you don't yet, you can start implementing them and find that you'll grow stronger both individually and as a unit."
Here are six phrases successful couples use, according to relationships therapists.
Saying, "It's understandable you feel that way," can be reassuring and show you have empathy, Morin says.
Persons:
Amy Morin, " Morin, John, Julie Gottman, Morin, I've
Organizations:
CNBC