Well, all these theories about why he hates being caled a coward in the first place seem totally possible, but I think the fact that he got so angry is because Harry himself was saying it. If the theory that Snape is good after all, the tremendous pressure of having to kill dd and then have the person he saved, the person that this is all about, the person he claims to "hate" so much and who hates him so much when underneath he is on the right side call him a coward...
Pressssssssssure
![:-)](./images/smilies/icon_smile.gif)
Poor Snape.
I suppose we'll all be gobsmacked if he turns out to be ultimately evil
Jaikai°