You two were having a fight. After being in the party and he being too close to other girls. It made you angry and after you two came back home you started a fight. He was trying to say that he didn't care about those girls but it wasn't enough to calm you down. He was tired of arguing with you so he suddenly Raised his voice. "You're making me sick! I don't know why i decided to be your boyfriend...You're proving how invidious you are! How can you think that you are a good person huh? Don't think you're so wonderful...you are such terrible girlfriend... I'm really regret of being with you"