Hi Happy Dude
reading your post I get the feeling that you have two dilemmas:
- your rhythm compared to others
- handling interruptions
For the first in my opinion this is normal, I love working late night and my partner loves waking up and handling his day in the first 3 hours in the morning (what creates some problems, as he is ready to have fun while I am just starting to warm up).
About interruptions I fully understand you, as I work from home and the distractions seem to be everywhere....
In the last 5 years with GTD and with this job working from home office and travelling a lot I found out that people that live in your house can be "educated" if you really want it and if you work consistently on it.
In my case the kids (15 and 20) know that if we are on the phone anywhere in the house (my husband also works from home), they have to be quiet. It already worked quite well when they were younger. If the door of the "home-office" is closed, no interruption is allowed. Of course it takes some time to have this working fine, but at the end...
...it is only YOU left to handle. And I found out that THIS can be the real challenge!