Man goes to girlfriend house and catch her with man and kill both of them cause she mislead him.

Man shows up at girlfriend house unexpected and front door was unlocked, when he walks in he hears girlfriend tells live in boyfriend that she cant wait to get married to him and that she loves him and only him. This man goes back out to his car and retrieves a hand gun and wait for the male to come down stairs and shot him 4 times in the chest, the female is still missing at this point.