Protector, guardian, brother, friend. Judas considered himself all of these when it came to JC. Sure, he watched over the rest of the Twelve, even the ones who were older than him, but there was a connection to JC in a way he couldn't explain. Soul mate definitely might have been the closest thing he could have found to it, and in the end, he had no problem in hearing it from JC or thinking it in his own head, but it would have been very difficult to say aloud. Affection, in any sense, wasn't something he was easy with.

"Your mother," Judas pointed out, easily holding JC's weight up, "is someone who I can't even imagine getting mad, never mind you. She thinks the world of you. She might get sad about it," in fact he was certain of that, "but not angry." Mary loved her son in a way that Judas couldn't even find himself being jealous of, not when she was such a kind woman.