Changing My Sanity

Before I saw the sun shine
Before I saw clouds roam over my heads
I seemed to actually understand joy
It was genuine for once

But that was then and this is the now
Sunny days never last for long with me here
They all eventually fade into something that kills
Rain clouds pelting me with raindrops
Thunder rolling in right on cue

Why does all the happy things fade away
Why do the sorrow and anger ruin everything
I dont get the simple things as these
Can someone help me?