There have been a far bit of talks during about what is happiness after the much publicity about Bhutan royal wedding and at the recent Singapore parliamentary sessions.
I have also asked myself numerous times in various stages of my life what is happiness for me. When I was sick and struggling to help myself to basis daily needs like eating and walking effortlessly then, my only wish and happiness to me is to able to do these basis tasks independently. Health is the only thing that matters then. Life seems so simple at that moment. But being human beings, we have an insatiable appetite. Once we have health, we take it for granted and want more of other things - self-esteem, beauty, love, money, status, power, fame.... etc. We keep thinking only when we have these things we can be happy. And we keep wanting and wanting, with the thought that we need more of these "things" even though we have already have the other things.
I suppose as human beings, looking for ways to satisfy one's needs is our innate nature. No one is spared from this, not even for people who are seeking enlightenment or nirvana (which I intepret as freedom from all worldly concerns). Englightment or nirvana is already a want or a need for that person who are seeking for it. It is not wrong to seek ways to satisfy one's need. Guess things start to go wrong and people feel unhappy when the needs and wants of a person become excessive and the act of seeking these needs by that person have inflicted pain/hurt to others.
I think a main key to happiness is the ability to feel contented and feel blessed with things that we already have. It does not mean we will stop learning and improving ourselves. But being appreciative of things and people around us, we are more likely to be at peace at oneselves (thus happier) and will be less likely to fall into the trap of "excessive needs or wants" and hence are also less likely to cause hurt to others in the search of our needs or wants.
Theory has said that SLE may be triggered by stress. People who are less satisfied with things or people around them are supposedly less happy and more stressed. So perhaps one way to overcome SLE or as a preventive measure is to first learn to be happy by feeling contented and blessed with things we have and not fall into the cycle of excessive needs.