Explain like I’m 5? Why do we say to stop intimacy at diagnosis even if monogamous? Like pre-antibiotic course

Don’t get me wrong I am not letting my partner get near my genitalia until I get a negative test. He’s negative after treatment and I never want to reinfect him! But I’m confused on why as soon as we test positive, we are told not to have sex. I’ve read so much in here but I guess not on this topic.

I understand if you’re single or polyamorous, to not spread it. But if my partner and I already gave it to each other and let’s say have to wait 2 weeks to see a doctor for antibiotics. I never said I was smart lol!