I agree with the previous poster. If they PT says not to exercise, I wouldn't do it.
As far as weight loss goes, the good thing is that the majority of your progress comes from diet, not exercise. So you can still lose weight consistently as long as you're careful about what you're eating.
Make sure you're getting some protein and/or healthy fat with every meal and getting enough fiber b/c all of those things help with feeling full.
"You may have a fresh start any moment you choose, for this thing that we call "failure" is not the falling down but the staying down." Mary Pickford