I Came To Protect You

I'm here to protect it,
but the bitter wants to infect it.
Push me over it, into it.
I'm falling here, bruised.
You tell me you need me,
well now I refuse.
I'm pulled to the surface,
and faced with my own lie.
Was is worth it to dive in,
to my send my heart in like coins in a bet,
to protect you from your own vises?
When you can't be trusted with me,
and your own devises?