|Run Malwarebytes, remove all it finds and see if that helps.|
Delete all cookies in case it resides there.
If just in browser, look at add-ons and remove anything you did not deliberately put there or want.
If elsewhere, run msconfig, start tab and uncheck that and anything you do not want to start with Windows, Apply and restart machine.
Look in Programs>Remove Programs and remove it if you see it.
You have to be a little bit crazy to keep you from going insane.