The Baxter (2005) on Netflix

Plot summary

A Baxter, in Elliot Sherman's own terms, is the steady, unremarkable man a romantic comedy passes over, and the label fits him: he works as a tax accountant in Brooklyn and has watched three girlfriends leave him for boyfriends from their pasts. Days before his wedding to Caroline Swann, he learns that Bradley, the sweetheart she had in high school, is back in town. Caroline tells him not to worry, and it does not help. His firm assigns him a temporary secretary, Cecil Mills, who refuses to accept that men like him are fated to lose. That night she sings her own songs at a small club and urges him to take more risks. Cecil argues with Dan, her boyfriend, who is not supportive.