Mine wasn't massive weight loss but I got up to 180 lbs which was the biggest I've ever been (I'm almost 5'10'') so I was getting into the overweight category and have always been pretty skinny. So I took this job doing field work in NY and over the summer (working 40 hours outside basically hiking) I lost 35 lbs and got back down to my goal weight. Even though I was only overweight for a short time compared to my entire life, it still affected me. I still felt like I needed to lose more weight even though I was at my goal weight. I saw fat where there wasn't any. And I notice stretch marks and bulges more than when I was overweight. It's weird how that works.

Maybe the reason you are having these negative images is because you are paying attention to your habits? One change in life style can cause an avalanche. When I quit smoking it affected my other outlooks. I started paying more attention to how I spoke, dressed etc.... You are caring about yourself for the first time and that makes you see those 'imperfections' even more. What you need to learn to do is to just turn those negative images into motivation. Not saying "I hate the way I look" but "I have a long way to go and can't stop now"

Also you have to remember that weight or BMI is not necessarily a reflection of your health. My boyfriend has always been so down about his weight. He works out and doesn't lose weight. But he can run a 5k in 20 minutes at a steady pace without running out of breath. That, to me, is the reflection of health. I might not be at the weight the BMI index says I should be, but I can do pilates and yoga for an hour straight with good form and not feel tired so I have learned to be accepting of my weight. Just keep up the good work and good luck in your journey! You will be so amazingly proud of yourself and are an inspiration to a lot of people!