i need help

ok, so this dude at work... i need to set some boundaries with him and let him know that it's not acceptable anymore for me to be his whipping boy when he gets mad about something and needs someone to take his frustrations out on. he really is the only sticking point to my finding this place somewhat bearable and now i'm starting to get my hyperventalation attacks again because i KNOW that i need to say something about this, but i don't know what to say and i just really don't know how to stand up for myself in situations like this.
he yells and gets huffy for no reason and then, when he's shown to be wrong, he doesn't apologize, it's almost as if the treatment gets worse. and now that i have 6 other loan officers to work with and look after, i've jsut come to the end of my patience with it.

so, any suggestions or advice would be awesome. :)

i need to do something about this soon. this is the first loan officer where he's so snarky (and the idiot is snarkiest over email) that i've started a separate "snark" folder for all the shitty emails he sends me. he is abusive and it needs to stop.