It seems that telling your partner you love them is not the key to a happy relationship.
Researchers at the University of Carolina found that saying 'I love you' is not nearly as important as saying 'thank you' in a relationship.
The study asked 50 couples, who have been together for roughly 15 months, to keep record of their interactions over one week - noting how appreciated they felt, and how appreciative they were to their partners.
Revisiting the same couples nine months later, they were asked to do the same thing.
And it seemed like they uncovered something.
Results proved that the couples who were thankful to their partners, and expressed that to them, felt more appreciated and were more likely to want to stay together.
Amie Gordon, a researcher with the study, spoke to the Daily Mail about the results proving the importance of being grateful.
"Feeling appreciated by your partner influences how you act in your relationship, and how much you want to stay in that relationship.
"Things start to go wrong in a relationship when you start to take your partner for granted.
"You get used to having them in your life and forget why you chose to be with them."
But Amie says it's the simple things that will make a huge difference to the longevity of a relationship.
“When you are appreciative and you notice the value in your partner, it helps you realise what you have and makes you want to hold on to it.
“You have something good and you think, ‘I want to keep it.’”