Come Home to My Heart by Riley Redgate

In a small South Carolina town, Gloria Forman belongs to her high school's popular Christian crowd, but since her parents threw her out for being gay she has secretly been sleeping under the school auditorium stage. Xia Harper skips class, keeps to herself and reads to escape, dreaming of somewhere being a lesbian wouldn't be a nightmare. An accidental friendship between the two grows into romance as they guard their secrets.