Welcome Hox!
Sorry that you’ve had so many infection issues…have you had the chance to consult with an infectious disease specialist? It is possible you have some kind of weird bacteria that is antibiotic resistant?
The other side of the coin could be to consult someone in the naturopathic end of things as well to see if there is anything you could do to build your body up to be stronger against infection. Some of us on this site including me use things like probiotics and cranberry pills and have found them effective, but as said it is best to consult with a practitioner to make sure that these things would be right for you. Take care and let us now what you find out.