The End Of My Family As A Family, Forever.

I haven't had any contact with my family for years.
This story is somewhat embarrassing and devastating, so maybe it will help someone from making my mistakes.
In my family, there was just us 4 my parents (since divorced) and my twin brother.
Being a biological twin (we were delivered by C-section as we were getting too big for our petite mother) I was born a full 90 seconds before my brother, so I always joked about being his older sister. Obviously as twins we were super close. We couldn't be separated at night for our first couple of years. Our parents tried, but we would both apparently cry if they tried to give us our own beds. They just let us sleep cuddling up with each other. We looked pretty cute cuddled up as babies. I still have photos.
My brother had a boy styled bedroom and I had an equally girly room. Everything was pink or purple. This was done by our parents at around 4 to teach us that we were not only separate people, but also separate genders. We were both fine with being different genders, but the separate people part was difficult. We talked about it when we became mature enough to appreciate what was happening back then. It hadn't really changed much. We both often felt like half a person in the absence of the other. We were often inseparable. Yes, there was therapy, counselling, psychologists and more, but nothing much kept us apart at night until we hit our teens and even then, I ran to my brothers bed for almost any reason. From being sick to just stop feeling sad and lonely. Nights alone were unbearable (they still are) without my brother. I'm not sure exactly when my love for my brother became unlike any regular siblings relationship that I knew. But at some point very early in life we began exploring and experimenting with each others body's. We worked like a single unit to keep this successfully secret from absolutely everyone and I know that nobody suspected we had crossed the line. As long as we were careful, nobody would ever catch on. Soon being in love was easy to hide and our sex lives became proper sex lives. We never used protection and my brother always came inside me. I have never taken the pill in my life or used a condom. I have also never been with anyone else. We were crafty, cunning, careful, we had rehearsals for what to do in whatever risky situation we could think of. We were the type that spoke for each other, spoke the same words at the same time without trying. We finished each other's sentences.
Anyway one day when we were home alone in the afternoon, we went from swimming to fucking in the backyard. Our neighbours were constantly looking over our fences to see if we were around to chat. If they looked right then they would have seen us naked on the pool deck with me riding my brothers cock like a cowgirl. After he came in me, we were both still really horny from the risky public service. I said, Let's make love on our parents bed?
My brother agreed (I knew he would), so we both ran off naked to their room, then both froze as the mailman almost saw us through the windows. This was more risky than the backyard. We couldn't close the wide open blinds for privacy, that would look much too suspicious during daytime. As the postman left, my brother asked if I was sure, so I said, We just can't get any cum on the bed. With that I hopped onto the bed and opened my legs for my brother. Moments later, he was deep inside me in missionary position. We were passionately kissing, breathing heavily, and properly making love. We almost always came together and this time was no different. Our orgasms began to build up and we both started cumming. As my pussy began contracting around my brothers cock, I felt his cum shooting inside me. I heard my father's voice. It was close too. He was saying my name and moaning. I panicked and pushed my brothers face away from kissing me, so I could see. What I saw was my father naked, wanking, walking towards us and saying my name. He wasted no time and hopping on the bed, he moved his cock towards my shocked face, telling me to suck it and I was a little slut. My brother hadn't even finished cumming, and now Dad had his hard cock on my lips. I always did whatever my father said. After he fucked my mouth for a couple of minutes, he pulled out and said to my brother,she gonna make me cum like tha. Get off her, Daddy's going to fuck his little girl and cum in her tight wet pussy. My brother pulled his cock out of me and within seconds my father was fucking me brutally. I hated it but it felt incredible. Just after a few minutes, he was emptiness nuts inside me. I hated what he was doing, but my body had other ideas. I began cumming on my dads cock, then my slut mouth kicked in, "Fuck me daddy! Yes daddy, cum inside me daddy! What was I saying? I didn't want this. I didn't even want my father to know I was with my brother. Next I hear my brother say, Oh fuck!. I looked over Dads shoulder to see our mother standing there.