I have that issue. I compare myself with women all the time. Even women who weigh much more than me, I find myself saying, "I wish I looked that good." I have no idea why, but I do. Like, the way they carry themselves, or the way their clothes fit... I wish my clothes fit nicely, or that I could wear makeup like that... etc...
I also saw a girl recently who had lost some weight. She looked like she had lost a little bit, but when she told me she was down to 5lbs BELOW my goal weight, I was disheartened. I feel so mean thinking that too.
To be honest, I have no clue what my body will look like at 130, 120 or 110. My ultimate goal weight is 110-115lbs, and I looked at her and thought that maybe I should lower it a little. But I keep telling myself that just because SHE looks that way, that I won't look that way. First, she didn't really work out, just restricted calories, so she wasn't very toned. She still looked "not fit". I guess that's what got me.
When I was 18 I weighed 130lbs, and remembered feeling a little chubby. So it just really brought back the fear that I might never achieve the level of fitness I want.