It’s called Higher Ground. Wikipedia describes it as following:
Pregnant, married, and awkward at eighteen years old, Corinne Briggs grows more and more interested in Jesus, eventually giving herself over to a radical New Testament church. Amidst her community of self-described “Jesus Freaks,” Corinne’s daily life consists of hours of Bible study, alternative family practices and bracing for the oncoming Rapture. It’s only when her marriage begins to unravel that Corinne dares to question the religious dogma she has embraced for her entire adult life.
And now I really want to see it! From the very beginning, it strikes a lot of memories for me.