Lyn and Elisabeth, first of all props to you for even talking about this when it's been a difficult journey and continues to have a hold on your choices to this day. I can get mildly obsessive with 'goals' myself, so I can just begin to imagine how much harder it is with an actual disorder. Stay strong, ladies! Especially you, Lyn, as it can't be much fun to weigh *other* people professionally while you're at it --- or does it act as substitution? (hope so)
Personally, I used to be a daily weigh-in girl for a year or so, starting with a weight challenge I was enrolled into at work. But one thing that taught me was that the numbers can fluctuate for all sorts of reasons, just as bloating can make your size fluctuate but not your weight! It did help to buy the scale, because denial isn't a great thing for someone like me --- I love to cook and I love food, and I absolutely hate *restrictions*, especially measuring calories and such. (Again, history of doing that obsessively from childhood to young womanhood --- but it eventually got old, thank goodness!) Now, I climb on the scales daily only *IF* I am actively trying to eat or exercise a little differently, to monitor the results --- or because I 'feel' different.
Otherwise, it's once every few days at random, not even planned. I can't exactly forget it for long, after all, seeing as it's literally staring me in the feet in the bathroom! I also measure myself with a tape measure every so often, again at random but maybe every few weeks? That way I'm keeping tabs, loosely, on both weight and sizes --- which for me is about the right balance between monitoring and obsessing. As it is, it helps me to stay alert to what I eat (or cook) without ending up at some cranky diet plan. (The official one at work involved the leek diet for two days a week! I love leeks, but UGH!) And I don't take changes TOO seriously, since I fluctuate a couple of kilos a month anyway!