should I let bank foreclose on home with structural issues

Help. I recently bought a house. I had a home inspection done. A few minor things were found and corrected. Since then I have found some major issues. I went into my crawlspace to insulate my pipes for the winter and to close the vents to the outside. In the southeast corner of my house I have found my floor joists are rotted/damaged and the sill is also rotted. Also, part of the subfloor is rotted/damaged and has started crumbling out and that corner of the floor has started to slope. I don't know if this is from dry rot or termite damage. The house was treated for termites but there was nothing listed in the report about structural damage. The problem area is underneath my kitchen cabinets so it isn't noticeable from the inside of the home. I went with an older (1963) home that didnt have any updates done because it was what I could afford. I thought it was a nice sturdy house that would just need new windows eventually and basic upkeep. I don't know what to do. I can't afford to repair it but I don't want to live in an unsafe house. Even if I could repair they would have to tear out the cabinets to repair the floor and joists I'm afraid they will find even more problems and it will get even more expensive. I don't know if they would have to jack the house up or not. Then I would also have to replace the cabinets and countertops. I drive a 10 year old car with 100,000 miles on it. I can't take out a loan for repairs in case I need to get a newer car. I couldn't afford both and I work in another town, I have to have dependable transportation. I bought the home for me and my two children and I don't know what to do. I can't put $ into a house if I don't have it. I wanted to make this a home for us but now I feel like I should walk away and let the bank foreclose. I worked so hard to keep my credit in good standing but I can't sink $ into a house that I don't have. I feel like I should just get us an apartment for us to live in and let the bank foreclose. I'm losing sleep and am suffering from depression from the whold mess. I don't know what else to do. Please help!