Is there a therapy center/retreat that focuses on food addiction? How can someone get funding to afford treatment?

YES. Weightwatchers is fantastic. Insurance company should be contacted if they'll pay for it -or a similar program.
Food addiction. I do not believe that patients are addicted to food. I believe that chemicals in our body cause us to feel hunger. Certain types of foods, like refined carbs, will cause our satiety-feelings of fullness- to decrease; we could eat more and gain weight. Since food is necessary for human survival, and typically addiction can be solved by stopping the addiction-difficult but possible; not addiction.
Yes. Over eaters anonymous has meetings in most cities and I think is either free or an as able donation. Formal programs will cost money and are easily located with web searches for your area. Insurance coverage is as variable as the ocean is wide. You could also contact the closest hospitals nutritionist and ask what services are available in your community.