It sounds like your girlfriend may be experiencing HPPD. I'm not sure, of course, but is sounds similar. I have had hppd at several times during my life. In the early 1980s I thought it meant I had "fried my brain" thanks to drug war propaganda, and being young and uninformed. It caused me incredible amounts of anxiety. I took LSD quite a bit, but never had HPPD until I smoked cannabis during an LSD trip. It made me so anxious. Eventually, I was so alarmed by it I stopped taking psychedelics for 20 years.
I should have just enjoyed the pretty colors in oncoming headlights and the swirling after images.
That's what I do now if I get it. I had it a bit a few years ago when I was taking a lot of dmt and mushrooms. I had closed eye visuals whenever I closed my eyes isn a dark room. My only complaint is that the visuals were dim and chaotic. Not organized. HPPD doesn't bother me if it happens now.
Be aware that dmt and other tryptamine drugs may trigger manic episodes. I am not bipolar, but I have started getting close to a drug induced hypomanic state, while in a phase of using extracted harmala on a daily basis and vaping dmt a few times a week.
Luckily, I knew when to back down. I felt great, but I was starting to believe in some strange stuff I wouldn't usually believe in. I'm usually fairly agnostic on all subjects.
I would encourage your girlfriend to read up on using psychedelics in combination with bipolar disorder. I know that people with bipolar have been helped by psychedelics, but I know the opposite has also happened. If I were you, I would encourage her to research and use caution.
I'm sure others with more solid info on bipolar and psychedelics will chime in,
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