There is nothing that any of us can say anymore. You have been doing this same dance for over 5 years now. It is easy to end a relationship like this but for some unknown reason you refuse to let it die. It will not ever get better. Stop looking for hints of a spark there and kick the bugger out!
The definition of insanity is doing the same thing over and over and expecting a different result.
You are your own worst enemy. If you want to have any kind of happy life - you have to change things NOW!
