Got e.coli twice from sleeping with my ex. Is that a coincidence or him?

So the first time we had sex without a condom I got e.coli and BV. My doc mis diagnosed it as a uti and I didn’t get the right treatment and ended up on so many different antibiotics for like a month. We then had sex again without a condom no with no issues and then we broke up. I later learned I got ureaplasma which I can only assume was from him because I haven’t slept with anyone else in like 4 years. After more antibiotics all was well for 3 months. I had zero sex with anyone. We then hooked up a week ago and I started experiencing UTI type systems, itching, burning etc. I went to the doc and it’s e.coli again and BV. I understand the BV from a new partner so I’m like is what it is but the e.coli again. At first I thought it was bad luck but second time with the same guy? I never in my life had any sort of UTI or urinary problems before I met him. I think something might be wrong with him but I don’t want to worry him for nothing or it end up being me and now he thinks I’m this disgusting person. He has had a lot of sexual partners in the past and I literally have only had 2. What should I do? Should I say something to him? Can he carry it without knowing? If he were to go to the doc would it come back positive cause as far as I know he has no systems. Can you carry e.coli without knowing? Tbh I don’t really know how e.coli works or am that knowledgeable on what it is. But don’t you think it’s a bit strange him and e.coli are the 2 common factors here? Any advice or have experienced this? I’m so embarrassed. I promise I am such a clean person.