Treatable but still awkward

So today I had my follow up with my gyno. I get regularly checked after every partner I have and I’ve always been EXTREMELY careful. Never gave head to Random’s, always wore protection, stuck to one guy at a time-type of girl. My current boyfriend is the ONLY one I wasn’t too careful with and today I found out my results came back positive for Chlamydia. I was tested last five months after my last partner and a month before my current boyfriend so it’s safe to say where this came from. How do I break the news without making him feel like shit?