(((firebird))))) sorry you are feeling sad and alone, afraid.... there is so much going on in your mind for you and how you manage to keep it all organized and from going in complete disarray is beyond me... no wonder you are feeling a bit overwhelmed at the moment....
im afraid i dont have much advice for you... stay in touch with your doctor and right now it doesnt sound like you are in danger of harming yourself, but suffering from the load you are trying to carry...
i dont mean to poke fun at you, having feelings of thought invasion and mind control are things that 'pop' into our heads and once there, what would a sane person do with them? i think you are being rational in imagining the 'what if it all were all true?' scenario...
just for the exercise, lets imagine that it all is true.... if the nanobots are invading your space then it s a real threat... there are many, but they are little, tiny in comparison to you... you are large and all powerful, a human.... you can (you must) dissuade their invasion.. you can do this through the force of sheer will.... simply tell them there is no space for them in the interior of your mind as that space is already occupied by stronger forces (your positive self image)
yes, you are much larger and much more powerful than a whole army of tiny gnat sized militia men and their ray guns and special weapons are the equivalent of tiny (albeit annoying) pin pricks against your leather tough skin.... they could attack forever and never leave one small insignificant wound on you or your psyche... so c'mon, get your power back... you can leave the couch (or wherever it is you are sitting) and go outside, catch some fresh air (nanobots hate that) and watch some kids play frisbee or fly a kite... heck, you might even want to join them (wouldnt the nanobots hate that?)
sending hugs and cares always friend