I’m so sorry you are suffering so much. You shared quite a list of diagnoses. I hope they are an outcome of a thorough and recent evaluation by a qualified mental health professional. If so, you need to go back to that professional for help that is specific to your age and situation. If you self-diagnosed, please turn to a professional for help at this point.
Part of the assessment should be a visit to your physician. At 55, your body may be going through some changes that are making you feel so much worse. Since you reported that you have felt a significant change over the last few months, it is all the more important to see your doctor. If there is a medical problem, addressing those health issues should be part of your treatment.
As for the mental health issues: There are evidence-based treatments for all of the diagnoses on your list. A counselor will help you prioritize what to work on and will help you design a program of treatment and support to help you feel better.
Please make those appointments. With good help, you can feel better.
I wish you well.