OMG I read this and said "THIS SOUNDS LIKE ME"
Some weeks I have weighed myself 5 times! I wish I could show you my journal (I've been doing this since 6/03. I've gone up, down, maintained.
I've had so many freak out at the scale sessions it's not funny. My boyfriend is thinking about starting to charge me for all the pep talks!
Starting this year I do log all my food into fitday. I spent so much time on Jenny Craig and WWs weighing and measuring my food, that I do have an idea now of how much I'm eating. I do think it's important to have a clear idea of what a cup of food is, or a portion. I struggle with getting too much into the diet mentality too, but being in a routine helps that. I take one meal a week off too, to eat something I might be craving. [I model my food by those two programs, with so many proteins, starches, fruits and veggies.]
For me, it takes a while to see what my pattern of weight loss might be, and that pattern changes over time. My periods never have been regular and vary from heavy to light.
The advice I would give myself (and you can decide if you think it would help you) is to lighten up and keep plugging at it. When I get to a point where I truly know I'm not doing enough, I know I have to tweak it (I usually start with more exercise and cutting back on extras that might have creeped in to the program -- sometimes I eat crackers at night when I feel hungry, or I have chocolates as treat, doh!).
I think it always will be a work in progress, so the more I keep track of my efforts, the more I can tell what I need to do to make it more successful (and I can be real about how much I am doing).
I hope that long winded reply helps!