Maybe this means Yamato can stop being such an empty headed dimwit. It's obvious he still wants to be with Suzuka, and the feeling is mutual, far as I'm aware. They need to just work their shit out and get back together properly.
He helped Yuuka finally confront her crush properly, and get over him. I'll be honest, if he's been seriously dating someone long enough to be engaged to that person, you'd think that would have come up at some point. Well, anyway, she's happily moving on, then.
But just because she's making a clean break doesn't mean Yamato and Suzuka are going the same way- there's clearly still feelings both ways, there. And, besides, he's basically cutting all the other ties as he goes out of his way for her. The other possibilities have pretty much removed themselves from the equation, acknowledging that he's still in love with Suzuka.