I am sorry

I'm sorry for everything you've been through
It must've been very hard on you
I'm sorry for all that's been said and done
I was the moon, you were the sun
I'm sorry for not making everything right
But the situation I was in, was very tight
I'm sorry for not lending you a hand
If only I could be a better friend
I'm sorry if it seemed like I didn't care
Lucky for you, your special- someone was there
I'm sorry for breaking your heart
For forgiveness, where do I start?