Can Anyone Help Identify What Is Going on Here?

Hi. I'm 53 years old. I have experienced insomnia on and off for the last ten years or so. I am reluctant, however, to use the term "insomnia", because it does not adequately describe what I experience. Frankly, I'm not sure I can properly describe what I go through during these cycles. It is not just a lack of sleep, although that is most certainly part of it. When I go through these periods, it is as if my brain is taken over by another entity during the night. I am force fed imagery that seems completely disconnected to my own mind. I am outside of the process, watching it all happen and fighting to not be a part of it. It is often repetitive and thematic, but offers no resolution; just the repetition of a grossly uncomfortable and indescribable movie frame. It is like a skipping record. This experience is not restful; quite the opposite. It sometimes is accompanied by flashing imagery or many, many voices all talking at once. None of them are mine, however. I am a reluctant (understatement) witness to all this.

Like many other threads on this page, there is a drug link here. I sometimes go through a phase of smoking weed. Not prodigious intake, but daily, and lasting for up to a couple months. Then I get tired of it and stop. Stopping can trigger these events. Also, I took Benzodiazepines for almost a year to help with insomnia. I took a low dosage and got off of it over a year ago. When things get crazy (as described above), I might take a 1mg pill to sleep one night. Works great; however, it also seems to intensify the above experience on succeeding nights.

I have poured through the internet to try and find anyone who can identify with this experience. This is not merely lack of sleep. Something else is happening here, and I am beginning to wonder if I am an anomaly.

Would appreciate any help. Thanks.