<human>: So a work friend of mine and I goof around at work a lot. He's an RN, I'm a CNA and we both work in a hospital. He's pretty good looking, but he's very aware of it and that gets *super* annoying. But he's funny and generally a good buddy.

One day we were talking about what we were looking for in a realtionship, and we both discover that neither of us is looking for a relationship, but both of us are interested in a sexual relationship with no strings attached. Badda bing, badda boom.

So we have sex once in March. It was not good for me, but I think he liked it. We made half-assed plans to go at it again, but he works straight nights and I work straight days, so it never ended up happening.

Then last month I started having vaginal issues (as my username suggests). I put off going to the doctor because I thought it was a UTI, which I get occasionally. But my symptoms wouldn't go away. I went in, got antibiotics just in case it was a UTI.

Then I get that phone call from the doctor who tells me I have chlamydia. He was my only sexual partner from the last time I got an STD check to this time. I got my medicine, but now I'm stuck....

Work buddy texts me and says that we both have Sunday off, and asked if I'd be DTF (not in those words; he beats around the bush a little, but we both knew what he meant).

How do I tell him that: 1) No, I would very much like to never EVER have sex with him again and 2) He gave me a pretty nasty STD.

The doctor offered to call him for me, promising to leave my name out of it so I would be anonymous, but I have no clue if I've been his only sexual partner in a while, and I really don't want him thinking that *I* was the one who gave *him* an STD. Or telling everyone that. Which I doubt he would. But who knows, you know?

Condense the text into a few key points
<bot>: FWB/coworker gave me chlamydia. I'm not sure how to explain this all to him, and let him know that our arrangement has come to and end, all while maintaining professionalism in the workplace.