Smoking Ecosport

I own a Diesel Ford Ecosport 1.5tdci Titanium TBA.

It is my own car that I saved up for, for a long time. At first it drove like a dream. It is now on 130000 something kilo's. For the last year and a half I've been struggling with a ball of white smoke coming from the back of the car, early in the morning and after work. It looks and smells like the car is going to explode. I took it to the dealership and back, made appointments about this and I'm always getting the same answer "nothing can be done" or "It is something in the diesel" or it just costs me money to find out what is wrong. I just want to know what is wrong with my car, because I drive about 60km a day for work, on my own, and what if something goes seriously wrong?

I love my car, but this was and continues to be, a serious concern every day when I go to work for the last year and a half