When I first met Rob, I thought my older sister, Clare, was so lucky to be with a guy like him; he was handsome, kind and so sweet to her.
Being the baby sister, I was only 19 when I first met him and he was 27 just like Clare. I idolised him but I never felt anything else for him except for admiration and when he married my sister I welcomed him into the family just as much as everyone else did. Everyone loved Rob.
Three years into their marriage, my sister got pregnant and they had a baby boy named Chris and they couldn't have been more overjoyed but that's when things began to go sour.
Clare developed post-natal depression and became increasingly difficult to be around. We knew it was a mental condition and we all tried to be there for her but Rob bared the brunt of it.
She was angry all the time and started throwing temper tantrums. She became so violent that she once threw Rob's computer out the window then tossed a kitchen knife at him telling him to get out of her face. Nothing helped, medication, therapy, she just kept getting worse.
I was over at their house all the time, I loved my sister but I could see the strain it was putting on their relationship. I was a shy, introverted girl and had never had a boyfriend. Maybe the odd kiss but I was a little awkward, I never had the confidence Clare had.
One night, I was trying to calm Clare down from one of her terrible tirades when she screamed at me, 'Shut up Teresa! I don't care what you think! You know, you should spend some time taking care of yourself rather than hanging around here. How are you ever going to get a boyfriend looking like that? You're just ugly!'
I couldn't take any more of her abuse and ran outside, Rob chased me as he saw that she had struck a chord with me, I couldn't help it as tears rolled down my face. I didn't know what was wrong with me! It was true, maybe I was ugly, and maybe I will never meet a guy who would want me.
I raced into my car but Rob was right behind me. He got into the passenger seat as I slammed the door. He tried to comfort me and tell me she didn't meant what she said.
I don't know how it happened but he put his arm over me, trying to comfort me and I looked at him and that was it. I felt something and I knew he did too. He's touch just made my skin heat up and I couldn't control myself. He lent down and kissed me and I kissed him back.
He had been needing affection and he wasn't getting it from Clare and I knew he always had a soft spot for me but I never knew in this way. But it was so intense, my desire for him was so wrong but so uncontrollable.
He told me that I was a beautiful and sweet girl and that any man would be lucky to have me. He just made me feel so good about myself. I couldn't help it.
We started an affair and eventually we fell in love. Clare started getting worse and Rob lost it when Clare dropped boiling water onto Chris when he was two, sustaining 2nd degree burns.
Rob decided to leave her then and fought for sole custody of Chris. He wanted me to leave with him but how could I do this? She was my sister. Three weeks later I found out I was pregnant.
When I told Rob, he was overjoyed but also worried about the effect it would have on Clare. My family would never believe I would have had a one night stand and after much consideration, I told my parents the truth. They went ballistic. They couldn't believe what I had done, especially to their favourite daughter. I was always second best, no one's favourite.
They refused to talk to me and barred me from their house. I knew what I had done was so wrong but I couldn't help who I fell in love with.
Rob won custody over Chris and we left. I was so sorry for my sister but I had a baby to think about now and Clare never showed any motherly affection to Chris. She needed to be taken care of and I knew my parents would do that but she wasn't fit to be a mother.
I loved Chris and would care for him as if he was my own. I gave birth to a daughter, Sophia and Rob and I were so happy. But I wasn't sure how we were going to tell Sophia one day that Rob was both her father and her uncle.
It's been 6 years since we've left and my family still refuses to speak to me. Clare never got better and was institutionalised with manic depression.
I secretly visit her sometimes, she never knew what happened with Rob, only that he left but I think somewhere deep down, she knew. I wanted to tell her I was sorry but I couldn't bring myself to tell her the truth.
I will always live with the guilt that if Rob hadn't left with me, she may have gotten better...
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