cheated by my boyfriend ?

it was a rainy day when I was coming back from my work. I didn't had any umbrella so I was all wet. but I am happy because my boyfriend Jack full name jack wiston he is waiting for me home today is our anniversary . I was in my home when I saw something unexpected . I can't believe my eyes my sister and my boyfriend together .I can't take it I left my home .It was still raining . I was crying in anger .Diana: why why ? we have known eachother from our childhood . why do you have betray me ?