Nobody is happy all the time. I agree with Tani. You can't appreciate happiness if you've never experienced pain/difficulty. Night follows day they say. Striving for happiness is doable. Happiness is first a study and then a practice. The same for any habit worth doing. There are books and audiobooks on happiness. There's actually an app entitled "Gratitude" and its so simply but works. I wrote an entire book, "The Art of Achieving Happiness" (Amazon) in this area. That's how intrigued I was and I've read on the subject for a few years now. When they say happiness comes from inside you, it's so true. Another thing are memories versus buying things. Meaning it's better in most cases to go on a trip or something versus buying a new stereo or car. Memories are priceless later on.
People know more about their limitations than they do their strengths. Most are thinking about tomorrow and never live in the moment. Start living and just be grateful.
I wanna see a person who is always happy. If one says one got happiness for eternity then one is lying if not then one his crazy. Happiness has its meaning because of sadness one value it because of sadness and one desires it because of sadness. So if you are sad because of failure and if you are sad because of broken heart or for any reason then happiness is your destiny and when you have it you know what you have. Enjoy that moment and don't think about its durability.
Why would you want to be happy all the time? We shouldn't deny ourselves the right to feel and express every possible human emotion simply because it feels unpleasant. If we don't get upset, mad, frustrated or jealous, then we are not really growing or learning.