WEST BRANCH, Mich.—When she graduated from high school, Taylor Tibbetts was a bright star in this small Northern Michigan town. She won an $18,000-a-year swimming scholarship to Converse College in Spartanburg, S.C., and departed for her freshman year with high hopes.

Once on campus, however, she felt overwhelmed by her courses and scared and isolated among students from all over the country with different values. After just a week, her mother reluctantly agreed to bring her home.

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