P.S. Anata o Kokoro kara Aishiteimasu. ~Saigo made Kizukenakatta Tsuma no Kurushimi~

The main character is happily married, but over time, notices his wife growing distant and reluctant to have sex. He returns from work one day to find her in bed with another man. Not listening to her tearful denials, he quickly hands her divorce papers, and the couple splits. Soon after the divorce, his ex-wife disappears, but he receives a DVD in the mail along with a letter explaining that the DVD contains "the truth" of what happened.