@adriana28 I'm 57 so I've been on this train for decades. I've been fat, I've been fit, I've been skinny fat. At 5'0 and at my fittest ever (running marathons and strength training 5x a week), I weighed 127 lbs but wore two sizes smaller than I do now, at 120 lbs and working my way back to fit. (And no, that is not due to vanity sizing: I have always tracked my measurements so I know what they were at 127 lbs).
I've done the 1200 calorie thing, weighing and measuring every morsel. It makes me miserable. Sure, I lose weight (got down to 97 lbs) -- but I just become skinny fat because I have no energy to do anything but lay around. It's unsustainable. And I really don't want to know the damage it's done to my bones over the years.
MyFitnessPal and calorie counting were helpful in that they taught me proper portion sizes. And also taught me that it is normal for one's weight to fluctuate -- whether it's because of hormonal fluctuations or the volume of food eaten or the sodium in the food. That's all good information to have, but once you master that, it's time to move on.
The older you get, the less important aesthetics become. Now what I care about includes: 1) Is my cholesterol dropping (yes!) 2) is my doctor happy (yes!) 3) can I carry my own suitcases and lift them into the overhead bin without help (yes! And I can also carry my husband's suitcase too!) 4) am I mobile and flexible and does my body have less pain (yes!) 5) can I hike or walk long distances (yes!).
I would be thrilled to gain 7 lbs of muscle and be back at 127 lbs, which is nearly overweight by BMI. But I know I was fitter than ever then and yes I looked great too. Because the scale does not tell the whole story!