I found the end of the episode remarkably poignant, actually. He’s failed; he blew it. Now it’s finally hit home, and I think the point of the entire proposal episode was to drive that nail into the coffin; J.D. has lost Elliott forever.
This presents the show, which is now almost certainly coming back for another season, by all reports, with an interesting opportunity; can they resolve this issue the right way (make J.D. grow as a person and resolve his lonliness with the right individual) or the wrong way (some contrived way to prevent Elliott from becoming Mrs. Dudemeister, and instead make her Mrs. Dorian.)
I am reminded here of the “Friends” resolution to the Ross-Rachel issue, which was done three or four years too late, but anyway, there’s an example of doing it WRONG, and I’m gonna get back to Scrubs so bear with me. The entire problem with Ross and Rachel was that Ross was immature and selfish. They had an opportunity, at the end, to resolve that issue; make Ross get on the plane and go to Paris with Rachel. All they had to do was have him say, “I don’t want to stop you and your dreams, but I want to be with you, so I’m coming to Paris wth you and Emma, and maybe we can make it work there.” Then, Ross would have shown that he had grown and truly wanted to do what was right for his family.
Instead, they had Ross beg Rachel to say - and, in effect, give up her career and her growth as a person to accede to Ross’s completely irritating and unsympathetic nature. It was a solution that made both characters regress as people. They’d be divorced within two years.
So getting back to J.D., you CAN’T get him back with Elliott without essentially negating all the growth of Elliott Reed and negating any chance J.D. will be a dynamic character. Elliott, who’s a nut case, has in fits and starts grown up as a result of her relationship with Keith. J.D.'s problem, at heart, is that he’s needy and self-centred. He doesn’t seem particularly interested in providing anyone else with anything; he wants Elliott when he doesn’t have her and is bored with her when he does. He wants attention from Turk, he wants Cox to be his father, so on and so forth. If you give him Elliott again he’s just getting what HE wants, and of course the relationship will fail again.
So to resolve the series what really needs to be done is to have J.D. get into a relationship with someone where he wants to give THEM something. Maybe Kim can do that, I dunno, or maybe Keri Russell can. But Elliott isn’t the right answer.