One question, Laura -- how tall are you? If you're at 139 and not happy, I'm guessing you're not too tall? I am 5'8" and currently weigh 156 and am a size 10-12. Are you wanting to be a size 0-2?
I also think sometimes we are too hard on ourselves. I have been really hard on myself lately, and I found some old pictures of me before I started to lose weight. It made me realize that I do actually look different, even if other people haven't noticed. I could see the difference myself in the pictures. I think perspective is everything. Change your perspective! Be so proud of yourself for losing 20 pounds and know that your heart and lungs are so much healthier. I think sometimes we all scale-obsess. True, that is a good way to measure our success, but I'm with Katie on throwing out the scale for a while. The scale isn't the only thing that measures our success or failures. We need to take a long look in the mirror and not be so hard on ourselves. Easier said than done, but you just have to hang in there!