We are all very unique individuals, with different ways which we offer love and receive love. This is sometimes referred to as love languages.
The wife's language might be words of appreciation and the husband's might be acts of service. He is working to provide for the family and to him, it is an offering of love. She complains that he never offers appreciation. "I told you I loved you the day we got married, if anything changes, I'll let you know," becomes his attitude. They gradually move into a state of disconnection and live in parallel, separate worlds. If they made an effort to understand each other's language, the dynamic of their marriage could be transformed.
If he offered words of appreciation for the small actions she regularly does and if she spent time helping in something activity that is meaningful to him, their relationship would become much healthier.
Here is quiz both you your spouse can do to cultivate a better understanding of each other to foster a better relationship. It's called the Five Love Languages.