Sounds to me like your workspace tag file is never getting finished. So it restarts when the workspace is again opened, never completes while workspace is open, lather-rinse-repeat.
We'll want to see if there is some code file in your workspace that may be tripping up the tagging parser. Use the Project > Retag workspace... menu command, and in the dialog that comes up, deselect the "Retag files in background" and "Retag modified files only" checkboxes so that you can see the progress control in the foreground. If that retagging gets hung up somewhere, let us know.
You may want to go into the Tools > Options under Editing > Context Tagging, and turn off the "Update workspace tag file on open" setting temporarily so you can run the above foreground tagging.