Hi,
Your concern is you don't feel happy for quite a long time. It's important to feel happy from the inside. May be something is bothering you in your life which you don't really know. I would suggest you do regular exercises, enjoy something which you are good at, get enough sleep & talk about your feelings with your wife. Communication is something that is very important in marriage. Even after all this, if you still feel unhappy, then you should consult a psychologist who will then help you get back on track.
Next Steps
consult online for further discussion.
Health Tips
eat healthy diet, improve sleep habits, share your thoughts with your wife