Holden Cruze 2010: Diesel particulate filter issues

I like my 2010 Holden Cruze diesel, but I am frustrated with the DPF filter. The warning light first came on after two months. The dealer then explained what it was, but I was also shocked to read about the implications of not continually driving the car at reasonable revs for the filter to complete its function or risk severe engine damage. My concern is that on occasions the light appears after a long trip. Surely this is when the diesel particles should burn off. I have been back to the dealer who has been helpful, checked the filter and informed me all is well. This was after it came on three times in the one week! Luckily, I live in the country and can run it out. How do city drivers cope?