Congratulations on your success!!
DH is about your height and I think your doctor is probably right in terms of BMI. When I met him he was about 188lbs and I thought that looked too thin on him. He looked best at about 205-210lbs. Obviously, you have a different body then him but I just wanted to agree with your doc.
You know, you are so close to your goal that I think if you're happy where you're at now there is no reason to continue. Why not work on maintenance and you can always decide to lose more later if you want to.
FWIW, my goal of 140lbs is definitely NOT set in stone. I have a lot of other goals in mind that have nothing to do with the scale (although I definitely want to be at least 155lbs or less so that I'll be at a healthy BMI) so I figure I'll probably stop somewhere between 140-155lbs. I've been 140lbs before in my life and I was really happy there BUT I was a lot younger, didn't have kids at the time, and wasn't lifting so my body is quite different now!