I like them together. Not the most traditionally romantic couple, of course, but lovely in their own way. If they come back together for a longish stretch of time, it would be a classic sort of fairy tale occurrence: two unlikely people falling in love against all odds. I can particularly see a character like Emmett fitting this mold. He's a dreamy, optimistic person, with big hopes for his life. He wants something special---and what's more special than this hunk of a man that so many men and woman are mooning over?
This is not a short, passing relationship, and, aside from the obvious previews for next week's show, here is why it will endure:
Emmett acknowledges that he is falling in love with Boyd, and then the relationship seems to end. But the writers just got him back on his feet after Teddy; they didn't need to bring him down again if they wanted him sad for a future plot---he was already there. No, I think they will feed off of what just happened and keep going with the Boyd plotline and, hopefully, something good will happen.
Boyd won't necessarily leave his wife-to-be, but I think he will come around and start getting closer to Emmett because there's no reason to develop a character so much only to toss him off the show.
He is an unlikely sort of guy for Emmett to fall for, or, rather, he is an unlikely sort of guy to fall for Emmett. Boyd is homophobic and at first you probably don't like him. But then it is revealed that the homophobia, in addition to being a likely and common trait for an athlete, is a cover for the fact that he likes sleeping with men himself. When he and Emmett start to see one another, Boyd treads the fuck-and-run path. Then he starts to talk with Emmett and goof around. Then he starts to stay in the room with him, even though they have already had sex. He even kisses Emmett, a highly unusual thing for a macho guy who only wants to get his rocks off. Later, we see him briefly holding Emmett's hand while they are in bed together. Boyd has started to unravel and get comfortable around Emmett. The writers would not introduce any of this only to throw it away without using it.
I'm not saying I think they will fall in love, move into a little cottage, and live harmoniously for the rest of their lives. More than likely, if they do get back together it will go on behind closed doors again. What else can a person expect? Boyd has a career to look out for. But hopefully he will be able to take a risk and, even very quietly, make something more out of their affair. The ball is now in his court. Or field.