Tsuki ga Michibiku Isekai Douchuu - Extra 58: At that time, first Miracle (Before)

Before her rebirth, Song Ran lived a lone and miserable life. Her innocence and naiveness cost her fortune. Her family assets was wasted by the stepmother, and her man stolen by her very best friend. After she was reborn, having the scales fallen from her eyes, Song Ran learned from her mistakes. The first thing she needed to do was ride on the coattail of her man with a promissing future, Mr. Gu.

This novel is also known as Master Fu's Mysterious Darling Wife

She is the The Young Miss of Military family Shen, her face is peerless, her temperament is cold, and she is her family’s treasure, but isn’t accepted as one’s child by her mother;

He is The Sole Heir to the top giant Fu Family, his power is unparalleled, indifferent high-born, the captain of the mysterious military force, and the youngest commander-in-chief.

Because of her grandmother’s wishes, she married him at lightning speed. She thought that it was a marriage that she needed, but she didn’t expect to be greeted with his extreme pampering.

- Description from Novelupdates

Transmigrating into a poor and mistreated young lady's body, what will the craziest alchemist of the seven realms now do?