Maid of Honor (1999)

Things are complicated for Serena: she's to be maid of honor this weekend for a high-school friend she made love to on prom night; her partner of five years, Doniel, wants to stay home and have a quick fling with another woman; and, the bride wouldn't mind a pre-nuptial tryst with Serena. She prevails upon Doniel to come with her, and then, surrounded by wedding talk about lifelong commitment and dismissive remarks about lesbians by straight friends, she examines her relationship with Doniel. Could they commit to more than their present semi-fidelity? What might Doniel say?