Check out this page for some quotes on happiness. Here are a couple of examples:
"Joy is not a constant condition. Most people manage a settled cheerfulness, but this, no matter how admirable, has nothing to do with joy, which flashes suddenly on our darkness. Like the light in an El Greco painting, joy does not merely illuminate the landscape. It transforms it." Sr Wendy Beckett
"If what most people take for granted were really true?if all you needed to be happy was to grab everything and see everything and investigate every experience and then talk about it, I should have been a very happy person, a spiritual millionaire, from the cradle even until now?What a strange thing! In filling myself, I had emptied myself. In grasping things, I had lost everything. In devouring pleasures and joys, I had found distress and anguish and fear." Thomas Merton