I did EDI-LON weekly for 5 years. I found I did get into a routine (and it cured me of my inability to sleep the night before an early flight!) but it was still tiring at times. The biggest issue I found was struggling to compress my home life into the limited time I was at home, as someone else mentioned.

Gave it up 3 years ago; I travel perhaps a couple of times a month for 1-2 days at most now and to different destinations. I miss lounge access when I am on BA but that's it, they don't fly direct to 2 of my 3 destinations and I'd rather take shorter direct flights.