The Promise (1979)
Two college students, one from a rich background, and the other from a poor one, decide to elope. They are involved in a serious car wreck, with the young girl's face severely injured. In order to get the necessary surgery, the mother of the young man injured in the accident offers a deal to the young woman - to stay out of her son's life permanently, and in return, get the plastic surgery to restore her face. What comes after that is something none of them expected.