I’m sorry it has taken me so long to get to this - I have HUGE Gabe feelings, which is to say I adore him as much as I adore all the Commandos.
I don’t think he reacted well. I don’t think any of them reacted well. The thing is, they’ve done so many crazy things, pulled off so many miracles, that all of them have adopted this type of bubble mentality, a pretense that maybe they are invincible, maybe they CAN survive this damn war and take down HYDRA. It’s a little bit arrogance, a little bit desperation, and a little bit buying into the hype that comes hand in hand with Captain America.
And sure, they’ve had tight spots. They’ve had moments where they weren’t sure they were going to come back - moments where they weren’t sure they WANTED to come back, but they made it. They’ve always made it.
And Gabe’s not stupid. He can tell something’s changed between Sarge and the Captain. The tension between them has shifted to something closer to anticipation and he even caught Sarge smiling. This mission’s no crazier than any other they’ve taken. It’s dangerous, horribly so, but no more so than so many they have already closed.
He sees the side blow out of the train before he sees Bucky still hanging on for dear life. He runs, forgetting for a moment the force of the wind around him and the sheer drop at his side. There’s no sign of Cap and he’d no idea how long Bucky can hold on for with the speed they are traveling.
He’s still two carriages away when Steve throws himself after Bucky. Gabe’s steps slow, almost relieved now because he knows Steve will move heaven and earth when it comes to the Sarge. That relief lasts all of seconds before Bucky falls, gone before Steve can finish screaming his name.
It’s autopilot that gets him through the rest of the mission. It’s Steve’s shock that sees him dispatching the last of Zola’s men and the mission that makes him step between his Captain and their captive before Steve can rip Zola apart with his bare hands, half expecting to hear Sarge calling out orders and talking Steve down.
It’s duty that gets him through to the end of the line, where the others are waiting for them, smiles on their faces when they see Zola in chains and horror in their eyes when only two of their team step off of the tracks.
Then it’s Steve who gets him through, Steve, who looks like he’s lost a limb. Steve needs them, so they hold fast, but their Cap proves what they’ve all long expected and fails exist without Bucky at his side. He’s gone before the ghost of Bucky has stopped hovering in the corner of his eye.
The war is over, and none of them make it home they way they hoped they might.