Dissociation is just a very creative way to cope with things that noone should ever have had to experience. Both dissociation and PTSD are normal reactions to abnormal experiences. I agree with what JA9W said and you are still you. You are just dealing with very difficult emotions.
Personally I think what you describe can easily happen with depersonalisation and dissociative trance states and blackouts like this are not that unusual even though I understand this is very difficult to adjust to and realise.
Realising how much we have or are dissociating can be a big adjustment so be really kind and patient with yourself. I was stunned and horrified at how I could have done something as long as I can recall and yet seemingly not have had any awareness of it at all. I still look at this and think :confused: We are not alone it seems that a fair amount of us who have significant dissociation have experienced it in this way.
Keep looking at charities as there are quite a lot in the UK and they tend to be very well managed and provide good treatment. If they are trained to deal with trauma they should be able to deal with your dissociative symptoms too.
What helps me is to think of the D as a helpful indication of what is happening in my mind and body, what situations and things are triggering, and what I need. Keeping anxiety down as much as possible and using grounding techniques can be very helpful.
You might also want to get a pebble or something textured to keep in your pocket that you can touch to ground you if you start floating off.
I don't have children but have heard many, many people say that they are what triggered the trauma to surface. Keep in mind that although it is a hard journey these things can be treated. Take care.