Books like Substitute bride by Margaret Pargeter

An undercover reporter follows a celebrity into rehab to uncover juicy gossip about her personal life.

ISOLDE WOULD RATHER WED THE DEVIL HIMSELF! For the odious Harold Biggelswade was, in her opinion, a good deal worse than the devil. But her avaricious guardian, Uncle Wendall, insisted the wedding would take place in three weeks. What was a poor desperate orphan like Isolde to do? Unbeknownst to her, a notorious rake, the new Earl of Shalbourne, faced difficulties tantamount to her own. For his formidable aunt Jane now threatened to exclude him from her considerable will (ruin!) should he not marry and produce an heir forthwith. So, reluctantly, he responded to the curious ad in the London Morning Chronicle, a desperate lady's plea for a savior—a substitute bridegroom. The wedding was hasty. The honeymoon, horrific, for the odious Harold was hot on their trail. But Shalbourne found Isolde an amorous armful—for a bride acquired through the morning paper!

A Marriage of Necessity Elizabeth Goldsborough was the happiest of young ladies. Not only was she the Incomparable of the London season, she was to wed the most handsome gentleman of the ton, the dashing Simon Bellgrave. Then, shockingly, all was stripped from her. An accidental encounter with the arrogant Captain Darius St. John left her with no choice but to wed this man she barely knew. Now she was a wife in name only in a marriage of necessity...trying desperately not to fall in love with a bridegroom who had asked for her hand out of honor but bad no interest in her heart....

A debutante who flees an arranged marriage swaps lives with a mail‑order bride bound for New Harmony, Iowa. In the frontier town, she must navigate rustic living, raise children, and confront the truth with her new husband—and their hidden pasts.