I can't be around forever

I try to help everyone who asked me for help.
And when people come to me for help, I never refuse; unless I dislike you.
But what are the chances?

Frequently I ponder upon my actions,
And I wonder if I am ever too nice; too nice to be taken advantage of.
It's fine if it brings people happiness,
But will you guys ever remember my contributions?
My presence, even?

Many times I picked myself up from the dumps,
Because to look behind is nearly pointless unless it makes you better,
In this case, I find only the fact that I am always giving.

What if, just what if,
I wouldn't be around to help anyone anymore?
I can't be sticking around forever.
I might die just tomorrow and noone will ever know,
No one will ever wonder about my existence,
Of course when people need my assistance but too bad it is just too late till then.