A Thousand Days' Promise (2011)

the leads in both film confess their feelings, make up for their mistakes and try to use the remaining time well after they know that one of them has a terminal illness.

Both couples go through a lot to be together and face an illness.
(BOTH ARE REALLY SAD).
Have a box of tissues ready

Matsumura Ryouko is a popular novelist in her 50s who has just found out that she has Alzheimer’s disease. In order to gain some fulfilment in her life, she decides to be a guest lecturer at a university. Through one of her students, she meets a South Korean exchange student, So Chan Hae. As they become closer, they fall in love.

Lee Gun used to be a promising tennis player, but he was injured. After that, he lost all of his self-esteem, and his life completely changed. With the use of a memory eraser, his memory is erased, and he is reborn with maximum self-esteem and presence. His first manipulated love is Kyung Ju Yeon, a psychiatrist at the brain research center. Other people around him include his younger brother Lee Sin, who is ranked the world’s no.1 ranked tennis player. Meanwhile, Jeon Sae Yan is Lee Sin’s translator.

Again if you just take it as a all then they don't have much in common if just the amnesia part. Ji Hyung is engaged to a woman chosen by his family, but he loves Seo Yeon, who he has been dating for years with the understanding that their relationship would last only until Ji Hyung’s marriage. The wedding date is set, the two break up, heartbroken Seo Yeon starts to forget things, first just the small one but its soon escalate to more important things that alarm her. As Seo Yeon’s memory loss becomes more severe, she learn an life shattering true and Ji Hyung must choose.

They both deal with the subject of lovers dealing with early memory loss and how it effects their relationship. Both are melodramas and acted extremely well. Heart tugging and lovely if you are in the mood for melo. Nicely done.

Both dramas are about Alzheimer's disease. In The Wind Blows, it is the male lead who's suffering from Alzheimer's, whereas in A Thousand Days' Promise it's the female lead.

A love story about a woman who falls in love with a man suffering from a split personality disorder, and the troubles she goes through because of this love. Aizawa Saki, who works for a trading company, was having an affair with her department chief, Okada, but decided she wanted to put an end to the relationship. On her way home after telling Okada it is over, Saki is surrounded by a gang of young boys. Luckily, Takagawa Ryo, a man with a piercing glance who happened to be there, rescues her, then steals some money from her wallet and walks away. The next day, a new employee, Mizuno Takumi, reminds her of him. Saki thinks that it can’t be the same man.

Both drama deal with Alzheimer's disease and its impact to the patient and their surroundings. They both focus on the emotional impact along with relationships before and after the diagnosis. While Memory focuses more on familial love, A Thousand Days' Promise deals with more romance.