Wow, it's amazing to come across this forum. My mum was diagnosed with postnatal depression when I was born, and spent the next 8 years in and out of hospitals being diagnosed with a wide variety of differing 'mental illnesses' ranging from bipolar through to schizophrenic. Eventually, when I was 8, she was diagnosed as having MPD, but was initially hospitalised and drugged due to her propensity to try an commit suicide. Over the following years, 32 different personalities emerged along with the horrific flashbacks, but at least the diagnosis made sense of the situation and allowed us to understand what was happening. The 'mum' that had looked after us until this point though, suddenly disappeared.
While one personality used to talk about the abuse, another was a small child who was very afraid of us and I used to read her stories through the door to try and soothe her. Another only spoke backwards, another was a guy who loved being outdoors, was amazing at DIY and loved to talk about plants. Others were angry and violent, especially when reliving experiences in flashbacks. I know my parents did the best they could to make things as 'normal' as possible, but looking back, though it felt like the norm, it was about as far from it as you can get!
As an adult, I am realising how much having to deal with these changes in personalities, parenting the parents and my sister, and hiding it all from the outside world has affected my own relationships. I am, like other contributors below, hyper-aware of facial expressions and body language, and have recently realised that I alway feel responsible for the feelings of others, particularly if they are upset or angry. Everything is second guessed. As a small child I know I inadvertently 'triggered' changes in personality and flashbacks, and wonder if this is a lasting effect. It has taken years to be able to acknowledge my own feelings and develop some sense of worth, but this recent realisation that I don't ever let anyone in and anxiety over even (or perhaps mostly) my closest friendships has knocked me sideways.
It would be wonderful to chat with anyone who has experienced this and worked out how to move on from it.