Tara, of course, assumes that Bill is dead because she doesn't know about how vampires explode when they die. Probably at some point once she has calmed down she will realize that Franklin Mott did not explode when she clunked his head off, but right now she is flying high and mostly just yelling. And in fact, this is key: Sookie only knows about that because of Longshadow, and Jason only knows that because of Eddie, and nobody else knows that. Because in this world, it is very important that people not know the infos of vampires, and vampires are the only ones that can give you the infos about vampires, if you see what I'm saying: Don't blame Tara for thinking that bashing someone's head into a paste is sufficient. Ninety-nine out of a hundred, I think you'll agree, it is.
Also, though, every time Tara calls Bill "dead" it's a double-entendre that strikes at the heart of Sookie, who has already stopped thinking of dead things as dead things, or else she would not have sex with the dead things. And finally, Tara is allowed to hate Bill a very lot. She's like the one person who has the right to hate vampires without seeming like a racist when she does it, because even if she was a racist before Franklin -- and Russell's house, and Talbot's lilies -- she now has more experience of vampires than Sookie, whose empirical evidence would suggest that what vampires mostly want is: To put the moves on you and then do you big favors.
(Also, remember please that Sookie only met Bill Compton something like six weeks ago, and is still very much in the flower of her love -- one thing I really respect about this show is how much it respects us by expecting us to keep up with the incredibly compressed timeline over the past three years, in which only once by my count have we "skipped ahead" -- so it makes sense that she is being so fucking insane. That, and the fact that she is fucking insane.)
The wolves are coming! Sookie doesn't give a shit. Tara and Alcide, seeing that Sookie is barely operational right now, wrap Bill up in a useful tarp and are getting ready to leave when good old Debbie comes twitching in there. "Oh, shouldn't have! Vampire burrito? For me?" (At first I thought she said "Oh shnap!" which made me miss Jamie Pressley.) She holds a gun on them, and Sookie tries to freak out even more, but I guess she's hit her limit on freaking out, so she just sort of vibrates. Tara, on the other hand, is on V, which Debbie is also on, so the vibe is really intense all around. (Alcide makes that one face.)