My Useless Husband is Actually the Immortal?!

The male lead is an immortal who has lived for countless ages. By the modern era, he seals away his memories and descends into the mortal world to undergo a tribulation. During this mortal trial, he marries into the Li family as a live-in son-in-law and deeply falls in love with the Li family's eldest daughter. In his mortal state, he once made a promise, vowing to give everything for her. Three years ago, his mortal trial ended, and he needed to go into seclusion to stabilize his foundation. Before entering seclusion, he regained his memories and instructed the immortal sage Fang Du'an to look after the Li family. Under his care, the Li family's wealth grew from millions to billions. Three years later, the male lead emerges from seclusion. Now, he realizes that he is an immortal, a being who has lived for millennia, while the Li family's young lady is no longer on the same level as him. At this moment, the male lead is transcendent, a celestial being—his tens of thousands of years of memories flood back, making the existence of the Li family's daughter seem insignificant. His emotions have faded. Yet, out of lingering sentiment for the love he once felt during his mortal trial, and out of a sense of duty and guilt, he decides to help the Li family rise to even greater heights. However, upon returning to the Li family... The woman proves ungrateful. What he once believed to be love and promises made in his mortal form are now seen by her as burdens, worthless—she believes he is no longer worthy of her. The aid he intended to offer is met with her mockery, disdain, and a demand to annul their engagement. The male lead sighs—if that's how it is, then so be it. Then, his true identity is gradually revealed, and the woman is left filled with regret.