Snape's not a coward. Maybe in the past, but not anymore.
First, read my response to the issue of whether or not Snape actually had to kill Dumbledore...
http://snitchseeker.com/vb3/showpost...&postcount=242
Okay... so I've established that Snape is not completely evil and pretty much had to do what he was told. Maybe you think it's cowardly that he followed through with his Vow and killed Dumbledore when he could have just died himself. Yes, I do think that is cowardly, but I also believe it took a lot of courage for him to follow through with it. If I am right about Dumbledore having a greater plan, than Snape would have had to kill him if he wants the plan to work and Voldemort to be defeated, hence the self-hatred he has for having to do this. Also, by murdering Dumbledore, Snape will now be seen as evil again, and that has to suck for him, considering he probably spent a lot of time trying to redeem himself already.
In the chapterd "Flight of the Prince," a few things caught my eye...
Quote:
"Fight back!" Harry screamed at him. "Fight back, you cowardly--
Snape obviously didn't fight back. He could have if he wanted to, and he would've had an easy time of it, considering how emotionally distressed and unstable Harry was at this point.
Quote:
But before he could finish this jinx, excruciating pain hit Harry; he keeled over in the grass. Someone was screaming, he would surely die of this agony, Snape was going to torture him to death or madness--
Was Snape the one torturing him? And if so, wouldn't it have been easier to just Avada Kedavra him? Snape was trying to escape, so why would he spend all that time inflicting pain on him?
Quote:
"No!" roared Snape's voice and the pain stopped as suddenly as it had started.... somwhere overhead Snape was shouting, "Have you forgotten our orders? Potter belongs to the Dark Lord -- we are to leave him! Go! Go!"
Oh, guess not. Snape wasn't even the one hurting him. Snape
stopped Harry from being hurt. Yes, maybe Snape was just following Voldemort's orders, but I doubt that. He probably is using is as an excuse for preventing Harry from being hurt and/or killed.
Quote:
"DON'T --" screamed Snape, and his face was suddenly demented, inhuman, as though he was in as much pain as the yelping, howling dog stuck in the burning house behind them -- "CALL ME COWARD!"
This really struck me as interesting. Snape seems to be is so much pain and self-loathing at this point, and is extremely angry at Harry for calling him cowardly too. Maybe he feels he was a coward killing Dumbledore instead of breaking the Vow and dying himself and doesn't want to hear it. Or maybe he feels like a coward because he's a spy and has to resort to sneaking around instead of just openly declaring he's on the good side. Or maybe he feels like he was a coward a long time ago, and does not want to hear that he is because he's a changed man fighting for the good side and it brings back painful memories. Or maybe he feels what he's been doing was a very brave thing, and he feels like he deserves credit for it, rather than being seen as a cowardly, trecherous snake.
Basically, while Snape's definitely not completely good or brave or noble, he's not completley evil, or cowardly, or devious. He's just like everyone else... trying to do what's right.