Hi Leela and welcome.
I agree with Karenina. I think protein shakes may help you lose but only if you use them as a substitute for a meal. At one point, I was substituting two meals a day with shakes and having a nice size low carb dinner. I was happy with the weight loss I had during that time. Maybe you could start by substituting one meal a day to start with, then if you aren't seeing any loss, or want to try to increase your loss, start doing 2 meals a day. However, you should probably check with your dietician before trying it, just to be sure they think it would be a good choice for you.
Also, earlier in the year, I lost quite a few pounds in a fairly short amount of time doing low-carb. Carbs were a large part of my diet, so the switch to low carb really helped me. Cut out, rice, pastas, bread, and sugary foods. And make sure you're drinking lots of water. I'm sure since you're in a diet class, you've heard all these things before, so I'm sorry if I'm telling you things you already know. I just thought I'd share some things that have worked for me. I have struggled with dieting for years so I know how hard and frustrating it is not to lose the amount you want to in the timeframe you want to. Just hang in there and keep doing your best, that's all you can do. If you want the surgery, just keep thinking positively and you'll get there. If you need support or more advice, come back to visit the boards often. This is a wonderful place for support and encouragement. Good luck to you and please keep us posted on how you're doing.
-Jenny