First of all, don't starve yourself because you're right - results are short lived.

Second of all, aim for a steady decrease in weight rather than a rapid one because results will most likely be permanent with a slower decrease. This means - don't try to do everything at once! Don't inflict exercise, meal restrictions, disallowing yourself from sweets all at the same time. Start one at a time, i.e. start by exercising every morning for 30 min. Once you get the hang of that, start putting limitations on your meals, such as no seconds, or chewing 30 times per each bite.

Then, once you get used to that, let's say after 2 weeks, start limiting yourself to one sweet per day, i.e. one block of chocolate per day or one pack of 100 cal snack per day. Gradually put yourself into a diet rather than suddenly altering your lifestyle altogether.

The fact that you're doing yoga is great! Keep it up, make it part of your everyday routine.

I hope you do well!! I have more stuff on my website, come visit sometime!
www.freewebs.com/myhappyforlife

You need to talk to you doctor and try to get off of these mood altering chemicals. Try psychologists, social workers, church leaders and in Germany they prescribe St.John's Wort; try it, it takes about 3 months to get it into your system so that you can tell if it is working. I helped me.
Have you ever heard of Oprah Winfrey? She has mega $. She hires people to research for her. Her findings recently were 3:
1. Read labels on all food products which are processed. If "partially hydrogenated oil" of any kind (vegetable, soy, cotton seed, corn) are in it as an ingredient, don't eat it.
2. Read food labels again. If "sugar or fructose or corn syrup" is higher than the 4th ingredient down the label, do not put it in you mouth
3. Walk. Get yourself a pedometer, one that will count steps. Wear it 3 or 4 days. Walk normal. Write down the total steps each day; then, after 3 or 4 days average it out and see how many steps you took per day on the average. Now, add 100 steps per day to this total until You come as close to 10,000 per day as you can get...if 7500 is as close as you can get the so be it. Walking in the cheapest, easiest to do, most proficient form of exercise available. Park in the fartherest spot away from the store and still be in the same parking lot and walk. Take the stairs, even if you work or school in a multi story building at least walk to the 2nd floor to catch the elevator. At the mall, take the stairs not the esculator. The weight will come off.
She probably has spent over a half million of her own money to find this out. She is most likely correct. Hang in there!