A good screen romance frustrates us, throws up comical or tragic obstacles that keep the lovers apart, and then provides a lovely release when those obstacles are surmounted.
But “Love, Rosie” overdoes that. It would be a maddening experience thanks to the many ways the hero devastates the poor heroine, if we cared enough to get mad.
Lily Collins plays the title character from Cecelia Ahern’s novel, a narrator we meet on a wedding day where she advises herself, “Tell them that this is, that this HAS to be, one of the happiest days of my life.”
She’s convincing herself, because she isn’t convincing us.
Alex (Sam Claflin) was the first boy she held hands with, practically her intended since they were in elementary school. In a years-long flashback, we see the ways miscommunications, unstated intentions, the weddings and funerals that have kept these best friends from being more than that.
There was the high school party where she had to get her stomach pumped, and the night she pretty much dared the virginal Alex to ask the flirty blonde classmate out.
He did, and lost his virginity. Rosie, meanwhile, had a sexual encounter with a condom accident. Their big plans, to jet off to Boston — him to med school, her to train to be a hotel manager — come to nothing. She can’t bear to tell him she’s pregnant, and holds off telling him she has a little girl.
“Love, Rosie” tracks them over a star-crossed dozen years (only the child ages) of bad timing, failed outside relationships, hard feelings and wedding toasts that reveal a bit more than the toaster should about his or her feelings for the other.
Collins (“Mirror Mirror”) and Claflin, of the last “Pirates of the Caribbean” movie, do well by the mooning over each other across a crowded dance floor stuff. But they have to keep us believing in “the dream” and hoping for their romance. They don’t.
There’s a little funny business, here and there, some of it provided by the “funny best friend” (Suki Waterhouse). Alex going to America changes him and his way of communicating with Rosie.
“Can we just forget the psychobabble and talk like ENGLISH people?”
But the watery chemistry, the on-the-nose choice of pop tunes to illustrate moments (An infamous Lily Allen hit, and “Alone Again, Naturally” turns up, naturally) keep “Love, Rosie” in the “Maybe we’d be better off as friends” zone.

MPAA Rating: R for language and some sexual content

Cast: Lily Collins, Sam Claflin, Suki Waterhouse

Credits: Directed by Christian Ditter, script by Juliette Towhidi, based on the Cecelia Ahern novel. A Film Arcade release.

Running time: 1:42