Why did I have to have a mother, a father, and a twin sister?

Why was I born in a family of 4? Why did I have to have a twin sister?<br><br>2 years ago, I found myself in love with my twin sister, and it has been the best 2 years I've ever had in my life. I was always happy. <br><br>Unfortunately, I didn't tell her about my feelings and I regret it till today. I didn't know how to approach her. My father was against incest, which made the situation harder. But I didn't care, nothing stopped me from admiring her. She was beautiful, she was so good with children, I loved her a lot. <br><br>I was expecting the thing to go on forever, but yesterday, she told me that she found a boyfriend. A 26 years old man, a friend of a friend, she met him at a party. She was excited to tell me about it. I was the first person she told. Obviously, I was shocked. I didn't say anything to her. Some times, I told her that she deserved a man. She's 21, it's time I guess, but deep inside, I was not happy. She didn't even ask me if I was okay. I am not happy. I don't want her to be with anyone else.<br><br>I don't think I can do anything about it. She's not mine, but I love her like she's mine. I'm not her boyfriend, I don't have any right to express how I feel. I don't know what to do. What would I tell her? "Hey, I've been in love with you since we were 19. I've always been in love with you." She's not in love with me like I'm in love with her, she's in love with someone else. I think that if I confess my feelings now, I will lose her forever. I will lose my best friend. We can't even imagine a relationship, we're twins, it's incest. My father will be mad. I don't know what to do.<br><br>Am I supposed to stay a secret admirer? I am scared to lose her, but I am also scared to be alone forever.