Luke wasn't all that oblivious to all those negative feelings, but he wisely ignored them for the time being because he supposed he could understand, in a way. It was a frustrating thing to not be able to communicate with someone. And it was a scary thing to give up something you loved.
Not that Luke was asking him to do that. Far from it, in fact. Which was something he was reassuring Grogu with even now.
He sat down at the table in the center of the greenhouse, folded his hands in his lap. "I have people I love," he said, not even all that offended by how invasive the question was -- it wasn't unfair, really. "Back home, I have people. I have a twin sister, and our friend -- well. He's here, too. And they aren't people I could ever stop loving. I wouldn't ask it of Grogu." Luke didn't agree with all the teachings he'd been given -- and he'd shunned his training for his friends before, even.
As for Ahsoka. "I don't know her. Jedi are scarce and I thought I was the last. Maybe she didn't want to be found, at the time."