I'd suggest not storing any food for later (buy just for one, two or three days, depending on how many meals you can prepare from food bought versus the cost thereof). Any stuff you don't have to buy in large quantities you should buy daily (preferably).

I'd also suggest going to the store to buy food by bike, running or walking. Going more often helps (obviously).

Then I'd suggest water and coffee or (black) tea fasting for a long time: absolute fasting with the exception of water, coffee and/or black tea, for 24-48 hours (48 preferred in most cases, but dizziness or really extreme headaches may be cause for going for 24 hours). Then you may eat during a few hours (say 6) and after that you again fast, but now for two-thirds of the time. Eat during a few hours then fast for a third of the original time. Then, again eat during some hours. Finally start over the entire thing and do this at least for a month. Being deprived of sleep due to this is no excuse (can't be that bad with many of the atypical antipsychotics). During fasting, try not to drink only tea. Water is best. Coffee might help with some "side-effects". Do combine this with (some) exercise, even though it is very difficult.

Lastly, I'd suggest (mild and controlled: use of an alarm clock and/or coffee/tea) sleep deprivation.

The last two are to "reset" your appetite instrumentation. Combining fasting and exercise will increase your body's capacity to store energy in other ways than by fat. The first is just common sense, but it may require some careful planning.