It's really

Heart aching when something you've fought so hard, for so long... Suddenly returns once again to destroy your life. Just when you though it would disappear and be excluded in your life, it just reappears. It doesn't die and evaporate out of existence. It's a weird feeling that not many people get (unless its sort of like a long-lived/waited sense of vengeance) but for me it's not really that since its not someone. 

Rather some'thing'. It could be psychological and it could be physical. I am yet to figure that out...