No you're not Kelwin. Things happen and people give up way too early on life when they have so much more of it to live.
You're definitely not a monster. Just a guy with too much weight and pain on his shoulders.
She is in Heaven now, looking down on the boy she cares about and I know she wants you to be happy and live your life.
Don't blame yourself.

The poem isn't that bad but I think it lacks a little more details to describe the situation more so people can have a more complete perspective on it.

Your expression hit me, hard, as all great poems do!. And YOU ARE NOT A MURDER, don't ever let anyone tell you that, you are an incredible person and please remember that. You have saved so many lives, so many of us wouldn't be ehre fi it hadn't been for your suport and motiviation, you encouraged us to live with your kindness and your AWESOME self!!!