dont worry, be, just, simply happy. How?
Try to find something good in every thing happens to you.
And dont overload you mind with the problems of others.
And, finally, dont EVER feel anger. That shitty feeling takes happines away, and brings pain.
theese are the things i figured out for myself. this MAY help you, or may not...

if it will not, think over you own definition of happines and find the way to reach it.

this is not a VERY optimistic song, but...
i think, you can find many usefull thoughts in it.

I know, I know I've let you down
I've been a fool to myself
I thought that I could
live for no one else
But now through all the hurt and pain
It's time for me to respect
the ones you love
mean more than anything
So with sadness in my heart
(I) feel the best thing I could do
is end it all
and leave forever
what's done is done it feels so bad
what once was happy now is sad
I'll never love again
my world is ending

I wish that I could turn back time
cos now the guilt is all mine
can't live without
the trust from those you love
I know we can't forget the past
you can't forget love and pride
because of that it's killing me inside

It all returns to nothing, it all comes
tumbling down, tumbling down,
tumbling down
It all returns to nothing, I just keep
letting me down, letting me down,
letting me down
In my heart of hearts
I know that I could never love again
I've lost everything
everything
everything that matters to me,
matters in this world

I wish, that I could turn back time
cos now the guilt is all mine
can't live without
the trust from those you love
I know we can't forget the past
you can't forget love and pride
because of that is killing me inside

It all returns to nothing, it all comes
tumbling down, tumbling down,
tumbling down