Ack, yeah that does sound like a difficult situation
. I don't know all the rules of the assistance you are on, but perhaps you could keep your earnings low by investing back into your business. Then you'll have a good thing going by the time you're ready to take the leap off public assistance. My business started small with basically no investment other than sweat equity, but now employs 4 people full-time and several others part-time. But even with a proven working business model, I realize there is NO WAY I could get a loan for 40 million. So I think you are going to have to think smaller. It sounds like you enjoyed the farm-sitting, maybe there is a future for you there? Or just pet-sitting perhaps?
One thing I have to address is that you mentioned your weight will increase if you stay on public assistance. Stop telling yourself that! Even if all you focus on for now is getting to a healthy weight, doing so will pay huge dividends down the road. I promise you'll have a better, clearer outlook, and the manual labor jobs you mentioned will be a lot more open to hiring you as well. Employers have to consider things like that because they have to look out for your safety.
So in short: Focus on the things that are under your control, despise not small beginnings, and try to think of creative (legal!) ways to maneuver the financial requirements of your assistance. I bet The Holy Spirit would be happy to help with all that if you ask Him!