>My existence is not just pointless but harmful.
That makes no sense, unless you are actively harming others that sounds like a nearly impossible thing.
>I know that you're supposed to be a new man when you accept God in your heart but my past has completely defined me and I will never be perceived as a human nor will fill like such.
You may be saved or on a path to salvation, that does not necessarily make itself apparent to other people. Then again, there are very few things that would define you so totally as to have that situation. It's not like you were a world leader that destined a 1/10 of its population to death for your own personal benefit.
>I always try to delude myself that it will get better but sooner or later it just falls even harder on me.
Well, do you have any bad habits you still haven't kicked? Perhaps there's something going on that is not meant to be repeated by you any longer.
>Everything is bothering me. Its not one specific event.
Outside of suggesting you see your shepherd and asking him for advice, I don't really know where to go from something that broad.