Can you imagine how scary it is to feel somebody completely, physically with your skin even when no one's there? To walk with them, to be where they are... To feel what they feel. To know untold things, I don't know how, but it's true. Feel somebody's emotions to 100%, never know where is yours and where is other's.
That's scary.
And painful, when you realise that it lives only inside of your head even if you receive 100% confirmation about everything... Brain can falsify this too. So you are trying to reduce that physical distance between you and others just to ensure yourself that you are sane.
That's hard. Really hard.
Now I understand why I shut it down years ago.