Hi luckygal
Recognizing that you have a problem is a good start and there are things you can do that will make your life better.
I would suggest talking to your doctor about your physical symptoms. My husband is diabetic and this can affect you mentally as well as physically. Insulin is a hormone, and when this hormone is out of whack as it is with diabetes, your whole mental situation can change drastically. Particularly if you are Type 2 Diabetic, and more so if your sugar levels go up and down or stay high. A daily monitoring device is excellent for you to keep an eye on your sugar levels. Anything above 7 is not so good and above 10 is getting dangerous. The added weight can drastically affect that too.
My husband just lost 40 pounds, slow and healthy, and it has made a huge difference to him. The Americal Diabetic Association can give you lots of good literature to read on this and your doctor can work with you. Also a nutritionalist can give you a great healthy diet, where you get to eat lots and are never hungry, but that will help. My husband did not realize that pasta and rice are like eating sugar straight. And that healthy drinks like V8 are also very high. Please talk to someone soon.
When you diabetes is under better control, you may find that your anti-depressants work better. Again, check with your doctor because if you take Metformin or other medication for diabetes, it can react with the other medications badly.
I was going to tell you to do some good things for yourself, things that make you feel better....but I have a feeling if you look after the health problems, the better attitude and feeling of well being will follow.
Good Luck and God Bless.