A story that gets going right away but runs out of gas

New story (I think it's a stand-alone but who knows these days?) from the always provocative and always puzzling Ben Lerner in current New Yorker, Ross Perot and China, gets off to a great start but lacks the sweet follow-through (will inevitably discuss ending of story in this post). I loved the story from and at the outset: a young guy entering the summer before he leaves his Midwest home for college in the East is out at night on a "man-made" lake with his girlfriend (whom he'll be leaving behind - whether because she's younger or not going away to school is not clear). Apparently he's yapping away oblivious, as too-smart young guys are wont to do, when he notices that she's disappeared. After some panicked moments of searching for her and calling her name, he starts up the outboard (some funny moments here as narrator recognizes his basic incompetence w/ machinery, contrasting w/ his many Midwest farm-descendant peers). He brings the boat to dock, clumsily and enters house of girlfriend's stepdad, goes upstairs in dark, takes a piss, gradually realizes: Wrong house (with an attendant shot at how much the lakefront houses resemble each other), sneaks back out, goes searching for his car, at least a half hour, finds it. OK to this point - he's surprised us at moments, made us laugh, kept us on edge. But we also ask along the way: Wouldn't he be in a panic? His girlfriend may have drowned, and he seems oblivious to that. But all is well, as when he starts the car, girlfriend appears from the house. At this point the story loses its momentum and the girlfriend goes off on a long jag about her life and about the interminable speechifying (on topics such as those mentioned in title of story) of her stepfather - an obvious hit at the boyfriend, too, as she apparently abandoned ship to avoid listening to his monologue (and he, like stepdad, was oblivious to his near-captive audience). They kiss, they recognize that at end of summer they'll go their separate ways, end of story. I have to feel that Lerner ran out of gas and didn't manage to bring his own narrative into safe harbor - or out to sea, as the case may be. We never get a sense of a what a crisis the narrator may have just avoided, nor does the ending produce any epiphany of realization or insight. Still, a story worth reading for its strengths - true of other Lerner works as well.