"You don't seem particularly inclined to share much, so I'm just asking the bit I want to know." Neville's tone was casual but if someone dug deep enough they would see the anger and the resentment there too. He didn't blame Snape for his parents, but he also knew the man didn't do anything to stop it, though he had tried to save Harry's. But it was all for selfish reasons anyway so he figured he shouldn't have expected any different.
"There's going to be another war. By the end of it almost everyone knows what you did. They call you a war hero, portrait at Hogwarts and everything." Neville did not dismiss what Snape did. He knew that without his being a spy things would have been that much more difficult than they already had been. But he still didn't have to like the man. His actions may have done good, but Neville still didn't think his motivations always had been. "I just want to know if you've gotten to the bit where you're not really working for Voldemort anymore. I think you have, but I'd like to be sure."