Sam has a plan. It’s probably a very stupid plan, but it’s a plan, and he thinks it will work.
After Brittany broke up with him, and after Regionals, and Mr. Schue’s wedding, he spent most of that night watching people. He watched Brittany go around to the group, trying to spend as much time as she could, but spending most of her time with Santana and Artie. He watched Mercedes and Kurt together, making each other laugh. And he watched Blaine. Blaine who kept trying to make a connection with Kurt, but who Kurt didn’t really seem to pay attention to. Which Sam thought was weird, because it was just a week ago that Blaine asked him to stay and he went to Blaine’s house, and they’d gone to Breadstix with the lesbian ring lady.
Something was up, Kurt was being weird and Sam is so glad that Blaine ended up not proposing. He’d watch Blaine go through being broken up with, and Sam was able to help him that time, but he doesn’t think Blaine would survive it if his proposal had been turned down. There’s no trophy to rescue this time. Knowing Blaine, he’d just run off to live with his brother in LA, and Sam needs him not to do that.