Some behavior issues scream unhappiness. If you're constantly stressed or finding that all your close relationships have turned rocky, you're probably already aware that trouble is looming. But sometimes the signs you're not doing so hot are subtle. A small change in your personality might signal that something deeper is going on.
Shying away from new experiences -- or even finding a lack of satisfaction in the experiences you originally found positive -- can leave you feeling quite negative about your circumstances. A University of Missouri study that quizzed 481 people about their happiness showed that participants who were able to appreciate a life change or a new experience for longer had a generally happier outlook [source: Wall].
This is also true for happiness in marriage or relationships. Couples who share novel experiences long after they've been together report greater marital happiness than couples who find their relationships routine. Simply participating in fun activities together, it turns out, makes us think of our partners (or perhaps even ourselves) as fun [source: Gordon].