"I don't. Don't hate either of you, you're great parents." That was why he was taking his mother's rejection so hard. Sure, she'd been exasperated with him before, and he'd gotten some lectures. But to be told--in less colorful language--that he was a fuckup... That was rough.
He only ever wanted his mom to be happy. If he'd been thinking more about his mother being here, and this being the first she'd ever seen of him, he probably would've cut back on the banter with Zelda and Hope. But he'd gotten carried away. Normally his mother rolled her eyes and ignored it, but he should've been on his best behavior. First impressions, and all.