Eating issues while depressed?

I'll start by saying that I do not have body image issues - I feel comfortable with my body and my weight. Under normal circumstances, I eat well and regularly.
When I get depressed, I feel guilty for eating so I'll go 24/32 hours without eating. I can feel that I'm hungry even though my appetite is obviously lowered and I know that I should eat but I just don't. I feel immense guilt for eating. Why is this? Am I the only one?