If married, resolve to nurture your relationship, to not take your partner for granted, to display to your spouse the sort of kindness that you display to others, to affirm your partner, to play together and share together. To rejuvenate your affections, resolve in such ways to act lovingly. Focus beyond the self. Reach out to those in need. But doing good also makes one feel good.
Compassionate acts help one feel better about oneself.
Count your blessings. Take care of the soul. In study after study, actively religious people are happier. They cope better with crises. For many people, faith provides a support community, a sense of life's meaning, feelings of ultimate acceptance, a reason to focus beyond self, and a timeless perspective on life's woes.