Happy doesn’t necessarily mean you’re jumping up and down from joy, but not being miserable does not mean happy. If all is well with you all the time, you will never really understand what true happiness is. Sometimes things need to get bad for you to appreciate the good in your life. When things get tough, you begin to wish to for what you had before.
I dare say that if you had all that you wished for in life, you may still not be happy because true joy lies in the pursuit, in the experience that comes from progress. Humans love the feeling that comes from achievement and will always seek challenges.
Happiness is acceptance of the current situation, been contented with what you have and where you are in life. But also doing the best you can to improve yourself in any way you can by giving yourself goals, and persevering to reach those goals.