system
A chat on 4chan
human
Best thing I can say is look through some of the other boards. If you believe its super natural, than you can fight it with super natural no? Maybe try practicing one of their arts/spells to see how it fairs. 

From most of these boards, they tend to say dreaming is a reality or realm that you have created, something that is tangible and real, so could make sense that an entity has wandered into this new place. 

If that's true, it'd make you the god of that realm. So you can expel it one way or another. Maybe try things that wouldn't let it control you, if you believe it has power over you, through fear or otherwise, can use it against that creature of sorts.

Or maybe you need better meds, I'm not sure really.
gpt
Thanks man, I'm currently rummaging about other threads looking for anything relevant. It's just odd that this just started happening recently... I've had periods over the years where weed wasn't available & dreams returned but they've always been normal. I suppose I'll just have to see if it returns tonight, and try harder to chase it off.