Demon Possession -SPOILERS-

There's one thing that I still am trying to understand or maybe I'm reading into it a lot. Now, everyone at the party, pretty much met some sort of gruesome demise once they became a demon:

Stooge getting his tongue ripped out to become possessed, the two kids in the coffin getting killed by Stooge, Sal trying to save Judy by taking down Angela & getting a stake in the heart, Angela with Sal falling down from the roof which for a moment showed her true self but bleeding, Jay getting his eyes gouged by Suzanne, Helen after landing on top of the car Rodger was in

Out of them, with the exception of Judy & Rodger who lived, Suzanne was the only one who didn't meet some sort of gruesome end. Wouldn't this have made them go back to normal once the main demon was destroyed ? It's not like they were all killed to become a demon or got burned like Angela or Stooge did. Any thoughts ?