Looking at all of this I have to say that while I don’t think you are a bad mom I don’t think you currently have the ability to be a very good one either. If you aren’t really able to provide your son with stable housing, regular food, the ability to leave the house and enough financial security (whether that is cash reserves or health insurance or whatever) to take care of medical necessities and you have no plan in place as to how to change that you might seriously consider either letting your son go live with his dad for a while if that is an option or finding another way for your son to be cared for away from your home. Send him to live with an aunt or uncle perhaps or get another loan from your dad to send him to boarding school for a year while you get your shit straightened out so he doesn’t worry about you constantly, or worse, think that your behavior is normal and to be emulated.
Seriously, please step back and read what you wrote. Your son is watching you attempt suicide. Your son is watching you spend weekends doing nothing but laying in bed. Your son is occasionally eating nothing but cereal because you can’t go buy food for him. Your son sees you being incredibly anxious because you have to come pick him up from school. Your son sees you neglecting your health. Is this what you want for him to see?
Lots of people hit bad patches in life. That is normal. Many of those people have kids. But if you can’t say that you have problems X, Y, and Z and you are pursuing solutions for all of them then this isn’t a bad patch, it is your entire life. You said in another thread how upsetting it is for you to see people not teaching their children proper nutrition to avoid obesity. Don’t you think it is just as (if not more) upsetting for a parent to teach a child that suicide is an acceptable choice or that spending days in bed hiding from the world is okay?