Thanks for the replies, they have been helpful.

Some replies seem to suggest a scientific explanation while others hint at maybe something more external. Once upon a time I would have accepted the scientific explanation, but I just don't know any more. As the days go by it seems the possibility of a metaphysical or even paranormal source for these thoughts is more likely to me.

Each person's past is a realm of division and subtraction because of the characteristics of that time structure. The past is evermore down and inward, from everywhere, toward everywhere, aimed toward the One infinitely kinetic, infinitesimal Singularity. Time is a medium and "material" into which exists... you and everyone, everything that existed during each instance of "the present". Your still there, the keyboard your typing on is still there, the Andromeda galaxy is still there, it's just down and inward from you.

To be in spacetime, being impacted by the time current out from the future, and to instead focus your consciousness there into the subtraction and division, causes cutting into the quality of each of your instances of "the present". Stop looking in the past. It'll eat you until you have no "present", even to the point you have no future.

i am thinking this..the bottom line is most negative thoughts come from this EGO thing...which seems to end up taking a life of its own somehow in your consciousness/brain whether out of fear or love...conditioning, programming,e tc

if someone has a better idea, please tell me