My PhD - Frustrations and lack of concentration

I am not sure what to start blogging about so I will start with a moan about my PhD.  I started this nearly 4 years ago and collected data.  I am tring to write stuff up - I find it hard to concentrate as I am also working and have a wife and 3 kids.  I find it hard to focus on the study.  I prefer watching TV or movies or just relaxing and having a good time when I am off work............The kids need allot of attention too.  However I need to push myself and get through this - its like a major goal in my life and unless I tackle it and finish the PhD it will always be hanging over me!