(Note: This statement is not on the questionnaire now, simply because I had to limit the number of questions to the ones that had been found the most common in the previous versions.)
When a twin is miscarried and leaves the womb entirely, this is a real abandonment for the sole survivor, and all other endings feel the same.
This came from a womb twin survivor in the USA:
I know I had my twin with me right up our birth, we were mirror identical sisters. As I was growing up I had imaginary friends and I sang myself to sleep every night. I would tell everyone about my twin. I was very proud of her and when I played with my friend I always had a baby that died. I had a favorite doll who had the same name as my twin. I still wonder what really happened. She's with me, I know that, but I look in the mirror and I sometimes think, "That's what she would have looked like."
The Black Hole is being abandoned and alone, unfinished, half formed, no longer whole. That is why goodbyes are so difficult - in fact endings of any kind are hard. This is why so many womb twin survivors find it hard to end a relationship even when it is going wrong. And it is so hard to believe that the other person will stay, that the anxiety and jealousy is likely to drive the other person away, and so the Black Hole is realised once more and you are alone.
In a relationship the beginning is wonderful but when it becomes closer and closer I have problems with extreme jealousy and fear of losing them. I react extremely emotionally and desperately to bereavement (in films, when my pet died, to others I do not know etc.) I have had a feeling of yearning all my life. In a relationship I have the desire to melt into the other. I hate goodbyes; I feel sick when someone goes away from me.