I really really really don't think you are losing your mind at all, just your footing perhaps.
For me it was very easy to get caught in the swell of telling. It's like being lifted off the ground by a wave in the ocean. I think it's called derealization or something like that and stress can cause it.
Whatever the reason, I've definitely felt it in my therapy, and outside of it too. The key is to ground yourself in the now. Touch something (I actually like to physically touch the ground). Look at something and try to account for every detail. Another great way to snap back to reality (at least for me) it to pick a word on a sign and see how many other words I can make out of the original word. It's a distraction, but it works.
True or not, are you getting the details right? You know, I don't really think it matters. What matters is trying to connect with how you felt at the time.
Suratji is right, the memory is fickle - easily tainted, but the mind and body remembers all too well.
For me, there are large chunks of time that I have absolutely no memory of. My dreams are filled with rooms that I can't go into and words that I can not read. It was crazy making until, with my therapist's help, I realized that it doesn't matter. What matters is the feeling, and those are hard to make up.
That person in the therapy room is you. You're here, you're alive and you're growing.
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