I Have IBS-D For Close To 1 Year. I Went

I have IBS-D for close to 1 year. I went to Digestive doctor and it helped for a while but keeps coming back. Should I be on an antibiotic? I have lost faith in the doctor. I also have Diabetes, Non-Hodgcans Lymphoma, Fibromyalgia and lost my husband of 50 years almost 1 year ago. I also have an Urinary tract infection. Every time I go to a doctor, they find something wrong. My health has fallen since my husband passed away, I am 74 years old.