I Killed You 'Cause I Had To (2008)

After a loner, Leo Breemer, who records his compulsive life through his video camera, misinterprets his vivacious next door neighbor's kindness for romantic love, he creates a pretend world with the unsuspecting woman as the sole object of his deadly obsession. Leo Breemer, under the guise of filming his new neighbor, Sima Reablo, for his "documentary", videotapes the trusting woman insistently. After stealing her trash and scavenging through it for "treasures", he discovers an engagement card and, psychotically, assumes it is proof of their forthcoming nuptials. Euphoric, Leo purchases a lavish engagement ring, honeymoon trip and "practices" the wedding day with the best man - his pet fish Opie. At the engagement party Leo is publicly humiliation by Sima's real fiance, Lukas; berated, furious and distraught, Leo murders Sima. And, post-mortem, they enjoy their first "date." However, the guilt of his crime becomes too burdensome, and Leo decides killing himself will be the only way to be reunited with his beloved so they can live happily ever after.