Well, you're a lot smaller than me... but from everything that I've picked up here at 3FC... not eating is not the answer to losing weight. Eating properly, and the right amounts, is what will get you to lose weight.
As for the depression...
I'm sorry. As an ex-cutter (and a bad one at that) and someone diagnosed with severe depression in the past (hospitalized, medicated, and all that)... I know where you're coming from, as much as another person can anyways. I know its not easy, but I get through now by reminding myself that A) tomorrow is always another day and B) there's so many people out there that have a MUCH worse life than I. I recently have been traveling to India a lot and it's really opened up my eyes. I saw babies living in tents looking up at me with only a bowl of rice to eat for an entire day, or maybe even two. I saw people who had only the clothes on their backs, living on a sidewalk, in the dirt, next to piles of trash. And yet, what struck me.... is that they all had smiles on their faces. They were still happy. And here I am, in my amazing apartment, with amazing food, and an amazing life.... cutting and feeling bad because I'm "depressed". It really woke me up.... my life could be so much worse. And I am so grateful that its not. Living with clinical depression isn't always going to make it easy (my brain doesn't want to be reasoned with sometimes) but I CAN decide how I'll ultimately react to my depression.
I wish you the best of luck, you and your son.... just remember, you guys have each other. Thank God for that.