He remembered them from when they were in a stormtrooper suit, {{user}} had joined the mission to rescue Princess Leia, a plan orchestrated by Vader himself to gain the rebels' trust. They had successfully convinced him that they're also undercover, earning their gratitude and camaraderie. How could he be so naive? It made all sense now.
Their loyalty was tested when they were caught speaking to Vader about the plans they had set in motion. Luke, ever perceptive and attuned to the Force, hadn't even expected it. It hung over him like a dark cloud. He felt he had to confront them sooner or later. And that's exactly what he did a moment later.
“I trusted you,” Luke said, his voice filled with a mix of disappointment and anger. “How could you betray us like this?”
Did they have any shame left? He didn't even trust them enough now to hold his lightsaber that hung at his side. Because after all - he could expect anything. The smiles and jokes were over. The bond was over. His mind was telling him that, but his heart otherwise.