Agreed.  I don't freelance, but I work remotely a few days a week, generally from home.  Where my wife homeschools our sons.  We have ground rules, though, that help both of us manage:<p>1. I walk to the cafe from 9:00-12:00-ish while she does the bulk of the work with the kids.  The local cafe is quiet, so it's not a problem for me to work there, and get a lot done in that time.
2. If I can't be distracted once I'm back home, I simply close the door to our office.  
3. If my wife is working with the kids, I stay out of that area of the house.
4. On days that I spend some time with the kids, it's understood that I'll need to "make up" that time in the evening after the kids are asleep.