I don't think BMI works either. I am 5'9 and weigh 143lbs, which according to BMI is ideal weight, but my bone structure is so slight that my ideal weight is 132 lbs (and this is according to my Dr. and my former personal trainer both). I carry most of my weight around my abdomen, which is still over 40" and she said that isn't healthy for me.
i think you should talk to your doctor. I mean, you say your ribs are very visable, yet you want to lose another 34#... maybe your husband is justified in his comments/concerns. someone can be 150 and flabby, and another person can be 200 and be smaller than the person weighing 150 because they are muscle. Talk to your doctor. assuming he's a good one, and ask him what he thinks.
I am 164 pounds and am still overweight-and my ribs and collarbones are plenty visible. I am hourglass shaped (plus a belly dancer) so my midriff is the smallest part of my body, but I am still overweight. My fat is just not concentrated in the midriff area-it is in my upper arms, buns, and legs.
An apple shaped woman can be just the oppostite due to her fat deposits being in her midriff and chest area-she can be at an ideal weight for her height-even a little on the thin side-and still not have "ribs show" (or collarbones) because of her apple body shape and fat storage in the chest and belly areas.