I've been experiencing huge gaps in my memory and am generally just confused on what to do.

for a bit of background on myself, I have CPTSD from some stressful childhood events that happened when I was really young as well as a Borderline Personality Disorder diagnosis.

recently I got in contact with an old friend I made in a really dark time in my life. we were talking and I confessed that I don't have a lot of memories from that time, we started talking about that and while on facetime she mentioned some things that I'm not really sure what to make of. she said that when we would be hanging out in the woods, I would just randomly zone out and no one could reach me for a while. usually this would end up with me just standing up with a blank facial expression and walking away while not responding to anyone or I would suddenly be very confused and uncomfortable with a lack of understanding what I was doing there. the times she said this happened line up with gaps in my memory.

I have other quite larger gaps too, like I don't remember 99% of what happened in middle school or my younger years in general. I also have moments where I feel like either I'm fake or the world I'm in is fake. it's concerning and I feel like I should mention it to my psychiatrist.

I've done research on dissociative disorders and dissociation in general, it seems like this is what's happening. I want some opinions from people who have dissociative disorders, does this correlate to anything I already have? should I be more concerned? how should I bring this up?