It makes some sense that Yuya would backslide into his bad old ways of thinking under pressure, feeling like he has to handle everything on his own, that he's the only one he can rely on and that he has to be the one everyone around him relies on. It's only been a few months since that changed and he still hasn't fully accepted the changes -- just look at how difficult it is for him to open up properly on an emotional level, to say nothing of the physical stuff, with the girl he's planning on spending his life with. And now it's so bad that he can't even do the talky-talk.
At least he's headed to someone who can literally knock some sense into him.