Barry, The Eternal Optimist
Barry had a rough go of things in Season 2, but don't worry -- he won't lose his optimism in Season 3, at least according to Gustin.
"We won't lose it," Gustin said. "I will be adamant! I don't know what's going to happen in Season 3, how they're going to write it, where they're going to go, but [Greg] Berlanti and [Andrew] Kreisberg and Geoff [Johns] -- I actually don't know how closely Geoff's involved anymore -- but all those guys know 'The Flash' better than anybody, and they know that he has to have the optimism."
"He lost his mom at a young age, he saw her right in front of him, then went back in time and watched it again... he'll find a way to deal with this [his father's death]," he continued. "He's not going to let it ruin him. It's going to be hard to come back from this one, but he'll stay optimistic Barry."