What does it take to be truly happy?

What is happiness??

Is it getting money and lots of it? Finding a lover? Getting your dream body? Getting a child? WHAT DOES HAPPINESS MEAN TO YOU? DOES IT EVEN EXIST?

As we all know most things in life come in two's, opposites if you may.
We get up and down, big and small, good bad etc. So having said that, it begs the question, is the opposite of happiness sadness? And if the answer is yes then does that mean that when you get the one thing you always said would make you happy you no longer going to experience the feelings of sadness?

Is it possible that we as people are selfish beings that simply want and want even more out of life? So you finally get the job of your dreams or the dream lover you have been fantasizing about, are you going to be eternally joyous or will there still be a void in your heart? Now some people say complete joy can only be attained once you give your heart to Jesus or God, may be so but then again there are lots of miserable christian people out there.

Well I do not know the answer to this question, if you happen to find out, PLEASE LET ME KNOW.