What would be a healthy weight loss goal for me?

anything more than an average of 2-3 lbs a week is unhealthy. You're looking at losing anywhere from 80-100 lbs in a year, its doable, but with a new baby, it will be tough. Its difficult to eat right when you're pressed for time, it's difficult to exercise when you're physically drained and sleep deprived. You will drop some weight while feeding, but a doctor will tell you, not to "diet" while feeding. You need to eat foods that won't irritate your baby, as well as foods high in iron and protein. It easy to say you're going to be gung ho to diet now. But once you have your baby to take care of, it will be the least of your concerns, try something a little more realistic like 2 years to get to 120 and a year to get to 150.