You know, I think its partially well meant comments but mostly a fear that brings these comments 'you are thin enough'.
Some really do see it as an innocent compliment, accepting us the way we are....but I feel like you that to the most part there is a jealousy involved and yes even the fear.
Not only that you may then be prettier than they, or wiill have mastered what they haven't been able to do as far as losing. But I also think the fear comes from not knowing "who" to expect once you have lost all that weight. Will you all relate the same way, will they/you look for different avenues, will you shine thru as successful now on the job as u actually deserved all along-which would hurt them.
I really think with weightloss comes a confidence and emancipation that we and the world around us have to get to know first.

I'd just tell them.....u aint seen nothin yet.....