Sorry to hear your plight,
But the good news here is that H.pylori induced gastritis is curable and yes you can lead a perfectly normal life after the treatment course, pertaining to strict adherence to the medication. You would also require some dietary changes during the treatment course. But yes you can be back to your normal state post treatment.
Secondly, H.pylori is actually a commonly found organism in the stomach in almost more than 50% of world population. But it does not cause gastritis in all of them, however in a person suffering from gastritis who has a documented presence of H.pylori, use of antibiotics can be beneficial. May be your physician felt that if after the 110 days if you still have H. Pylori induced gastritis changes may be he can start you on antibiotics. The Rationale here may have been to treat the patient not the disease.
Next Steps
If you still feel that antibiotics would be advantageous for you, get a second opinion with another endoscopy for Rapid urease test, or a stool antigen test for H.Pylori to check for disease activity