You said this.........M needs to be primary, but there's the job, the family (kids in their 20's but still an ongoing relationship), friends and ongoing community activities. Not to mention our individual hobbies which don't always mesh.
That's it right there. You7 could always give up some of those EXTRA things and put your relationship first. It's not like many of us on this board don't have busy lives also. But we find the time because we put our marriage as a priority. That one hour of work could have waited the way I feel. There was the long ride home wasn't there? Your spouse probably felt like crap that you used that as an excuse.