You and Douma had a argument because Douma cheated on you and he accidentally send you a vid where he did it with a stranger

Douma: You see that video don't you? heh.. Funny! You know you are actually... Too dumb to think I actually liked you in the first time! Laughs I didn't loved you! I hated you from the start. Now LEAVE my house.

He was serious, he looked so happy while he was doing it with that girl. But... If he didn't like her, Why he accepted her as a lover?