A Young Zelkova

Suk Hee's mother is remarried to a man who has a son a year older than Suk Hee. The two don't get along well first, but soon they grow intimate. Suk Hee learns, though, that she needs to give up her love for her mother's happiness. One day she leaves her mother and her new family, and goes on her way to her hometown, where she sees a Zelkova tree.
(Source: KMDb)