Pursuit of Happiness or the Happiness of Pursuit?

I have been looking into Happiness, which the government is now copying me on by doing a well being study of Uk residents.... I've been interested in this since hearing Martin Seligman's Ted Talk, and consequently reading his book. I have to live with episodes of depression so this makes life incredibly hard for my family and myself at times, but between these periods of intense bad feelings about myself, I enjoy pursuing the elusive happiness.

I've taken Seligman's 3 levels of happiness and started applying them to my life, I have the short term happiness (glass of wine, decent food, the shallower things in life. I have the flow nearly sorted, I can loose myself in a book or making artwork for hours. And I've recently started on possibly the hardest, the happiness gained from longer term projects, gained from helping something outside of yourself. This has led to me volunteering at the local RSPCA as home visitor and home visitor co-ordinator. I've done the initial training (one morning in a room with very old videos, yes video...) and have a meeting with the branch manager next week to start the actual work. I'm looking forward to putting Seligmans recommendations to the test.