On this page of the Assassin's Creed Valhalla guide, you will find a detailed walkthrough of the Historia de Cordibus Pathetic side quest.
Reward for completing the mission: 1200 XP.
In the place marked in the picture above, you will meet a woman who confessed her love to Aldwyn. When you talk to her, you will learn that the man is unmoved by her efforts and refuses to open the door from the house.
Now you need to instruct the woman on how to win the heart of her chosen one. When you advise her to talk about his beauty and charm, Aeldwyn will not open the door, the woman will leave, and the mission will end.
If you want to help a woman, say that you need to look around first. Under the shed on the rightn you will find a sheet of paper from the journal. Return to the woman and tell her to start praising her chosen one's beer.
These words will eventually soften the man's heart, and he will open the door to his admirer. It's worth giving all the credit to the woman and lie that she came up with it herself. Otherwise, the man will get interested in Eivor.