Thanks for your responses. It's nice to see I'm not alone in any of the concerns I've brought up in this thread

'DID-dar'! That's the right word! I read your thread on that subject, Una+, thanks, that's all very helpful. Yes, I've noticed with one person it's like magnetism - I felt a very intense dislike the first time I saw her, before we even talked and that changed quickly to the opposite and I felt we really related on some level that I didn't with other people but I didn't know what exactly. She said the same. We've had some very difficult interactions but it seems that's the result of switching on both sides. I feel I should go very carefully with her, but I have an idea of her alters and which ones would be best to talk to, if I'm patient. I also have the feeling some of mine have already been talking to her without me knowing. I'm not sure, but I won't hide or go into denial myself and that should help. With another person I have suspicions about it looks like it might be easier.
One is a family member who I've noticed thinking back has shown more obvious signs than I do, but it hasn't been picked up on by the mental health services. No one even mentioned trauma. I've met some very distinct personalities with different names and other signs like 'out of body experiences', losing things easily, very sensitive, changing life plans quite dramatically etc. Can't believe I didn't see it before. I can certainly talk about myself next time we meet though, we talk about everything that's going on anyway.
In any case, after reading the posts here and considering, I think I'd like to slowly become more honest with people in my life. If I have support from the doctors too I feel that would make it easier. We'll see how that goes.
I don't want to hide and pretend, I've had enough of hiding and running away and worrying about other people's opinions. Only worried about triggering other people but I can be careful with that.