I believe that there two types of BF'ing mamas: those who lose like crazy (lucky ducks) and those who hold on to every bit of fat. I, of course, hold on to it. I didn't lose any weight until weaning (and I tried WW nursing mama plan).
From an evolutionary perspective, it's probably better to be in our camp because in case of famine, you're holding on to your baby's food supply and baby is more likely to survive. i try to think positive!
Also to mamas who crave sweets, increase protein in yr diet. Sugar cravings are often a sign that you need protein. It happened to me into first pregnancy. All I wanted was CANDY. Discussed it w/ mw and increased protein intake. The candy craving went away.