At first I had that problem, people stopping by in the middle of the day because they thought 'working from home'/'self employed' was a pseudonym for early retirement. I have since created solid work hours (9:30-6:30ish) that I treat just like working for an employer. My family knows that within those hours I am as available/unavailable as I was when I worked for a corporation. I find that this puts me back on the same page as the rest of the world so during the evenings I am no longer running off to check up on something and whoever I am with has my full attention.