Happy Go Self-Harm

How I treat you, and how I treat myself
are like chalk and cheese, they're so different,
I seem to make you happy, but you don't
make me so, I have sins I must repent.
You say I put a smile on your face,
I add another tally to my arm,
you say I ease your pain and make you glad,
but to myself I can do naught but harm.
You notice not, and live your happy life,
the same with everyone who I have met,
I hope to see you smile, that is my wish,
but "will I live to see it?" is the bet.
I'm on the way to jumping off the edge,
but I'll refrain myself for you, I pledge.