Albert Barnes on 1 Corinthians 7:13

Let her not leave him. A change of phraseology from the last verse, to suit the circumstances. The wife had not power to put away the husband, and expel him from his own home; but she might think it her duty to be separated from him. The apostle counsels her not to do this; and this advice should still be followed. She should still love her husband, and seek his welfare; she should be still a kind, affectionate, and faithful wife; and all the more so, that she may show him the excellence of religion, and win him to love it. She should even bear much, and bear it long; nor should she leave him unless her life is rendered miserable, or in danger; or unless he wholly neglects to make provision for her, and leaves her to suffering, to want, and to tears. In such a case, no precept of religion forbids her to return to her father's house, or to seek a place of safety and of comfort. But even then it is not to be a separation on account of a difference of religious sentiment, but for brutal treatment. Even then the marriage tie is not dissolved, and neither party are at liberty to marry again.

(*) "him" "not put him away"