A 17 year old women gets pregnant accidentally and cannot tell anyone she knows. Her family are extremely Christian and her "best friends" are looking for drama in the school. She cannot ask for aid from anyone. She has no one. Then she discovers she cannot get an abortion in the state she lives in. That is reality for women that live in states like Missouri.
That is what the film is conveying: these decisions are difficult, they require proper support to come to the best conclusion for the women. She is deprived from this and makes a decision to drive a 1,000 miles. Who would want that for there kid?
A lot of reviewers are focusing on a "women getting an abortion is bad" and not thinking about what put her there to make that decision alone.