I work from home a lot, I find I get a lot more done at home rather than in work, so I tend to schedule days when I need to bury my head in data. All I can suggest is that you plan, plan and plan again, and do stuff in small chunks so you can mark off sections easier - this makes you feel like you are getting more done and then you are empowered by that to carry on.
Looking at having to do the whole disseration is probably what is makign it difficult for you, by cuting it down into sections, you will make it an easier proposition.
Good Luck!