KTna-I am going through the same thing. I was about 150 when I met my husband, and my highest weight was 211 after our two kids. Now that I am going back down the ladder-he has told me he doesn't want me to get too much smaller.
With some men it is a self esteem or jealousy thing-but in my case as well-my husband just prefers fuller figured women. Every serious girlfriend he ever had before me was fuller figured
ALL of his girlfriends in the past have been a minimum of a size 9/10-but most averaged a size 16-20. Very thin women who wear a size 2/4/6 ar 100% out of the question!

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He is a "butt man" and likes a big rear end.

That is just what he prefers and is attracted to. It isn't any sort of self esteem or jealousy issue with us-the women he likes on tv are ones with fuller buns and busts as well.
It is the same thing as my preferring men with brown/black hair, and brown/hazel eyes sort of coloring over men who are blonde and blue. (Just not attracted to the "Ken doll" look!

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