My advice is not to change any of your meds following your surgery. I take effexor for depression and have been continually improving each day. My depression was directly related to my obesity and the anxiety that I had from constantly worrying about what the obesity was going to do to my body (ie diabetes, etc). Once you start seeing the weight come off, you will feel better physically and mentally. Yes, you might "miss" food since many of us used food for emotional support. But when you start feeling better and your self esteem improves because you look better, your depression will improve also. Just remember, take it slow. There will be challenges but think about the future and what an improvement the band will be for your health.
I was banded in January and have lost 35 pounds. I don't have the dread I used to have when I got up each morning. Think of it as a challenge to do the best that you can possibly do for YOU. Put yourself first and look at the positive step you are making by going through the banding procedure. Think positive and the rest will follow. Best of luck!