What is your most recent memory of happiness? Can you remember where you were, who you were with (if anyone), and what you were doing?
Can you remember the smell, or the sounds around you? Can you recall colors, textures, shapes? What was it that made you feel happy at this moment?
Who makes you laugh the hardest? Who do you trust with your most intimate secrets? Who knows you better than you know yourself?
When you figure this out, make sure to let them know how special they really are to you.