I am learning that if I am unhappy the reason is most probably that I am focusing on what I don't have rather than what I do. I'm thinking thoughts like "I don't have great job, I don't have enough money, my parents didn't love me enough, my wife doesn't treat me right"... and on and on ad infinitum. I came to AA with a whole list of "don't haves" and 1001 reasons to drink. Today if I'm not careful, I can still get to seeing the glass have empty.
The way the universe seems to work is to give me what ever I focus my mind on. If I am thinking about how bad my job is the universe responds by giving me a worse job or taking away the job I have. If I think constantly about running out of money then I'm bound to face even greater financial problems than I already have. I'm certainly not going to get better treatment from my wife by focusing on her negative behaviors.
I think the other big book calls this "sowing and reaping." This is some kind of spiritual law that says I can have no other life than the one I think most about. If I'm planting mental stink weed seeds, I cannot grow Easter lilies. By the same token, if I am focusing on those things in my life I love and enjoy, the universe responds by giving me even more. If I want a better life I gotta remember to count my blessings.