I also broke 80 for the first time last week, with a 79 on my home course which is a very easy par 70, 5750yds. The course rating rating is 67, we don't have slope ratings here. So am I happy with breaking 80, yes very. Two months ago I was shooting high 80's low 90's on the same course. Conditions haven't changed, my game has improved. Will I break 80 next week when I play a par 71, 6800yds course with loads of water, probably not but I am hoping to be in the mid to low 80's.
So the moral of the story I guess is to just keep improving on your own game, keep improving on your scores which means you have to keep breaking 80...