I have since January lost 3.5 stone. I was VERY overweight, so am far from thin now, but I have gone from a good size 22 to a size 16 (ish). So still a way to go, but I do think it's a noticeable change.
I have had lots of compliments and encouragement from friends every time I see them and I am honestly very grateful and
about that. So it's not like no-one has noticed. But I work in an office of 50-odd people and barring one (who is a close friend as well as a colleague) not one bugger has said anything at all! Likewise my oldest group of friends (in terms of how long I've known them - we all went to school together - not their age!) haven't mentioned it.
I am a bit of a princess (pampered only child
) and am probably being a bit egotistical about it. Am therefore quite happy to be told IABU and should just get over myself 
Just think it would be nice if the people I spend upwards of 40 hours a week with, and the others who I've known for most of my life, seemed to have noticed! I'm always complimenting them on new hairstyles, colour, outfits, etc.