First, I am so sorry about your problems.
Second, I agree that you need to get another take about what is going on and what is required to fix it.
When we purchased our 2004 5 years ago, we purchased an extended warrantee because we did not have a complete set of maintenance records. We have not had anywhere near the issues you have had, but the warrantee has more than paid for itself. We will be getting another one for a few more years when this one expires. Diesels are reliable, but when something breaks, it is awfully expensive. People talk about doing the work themselves, but there is no way I am going to be doing jobs like replacing injectors. I can change my air filters and air dryer filter, and I can clean the radiator and CAC and jobs like that, but anything beyond that, I need to take it to a shop. Getting a shop you can trust is a challenge.
I hope this turns out OK for you.