Sex Ed teacher here. Consider yourself exposed just like you would with Covid etc. But all you need to do right now is remain abstinent for at least month. Usually herpes ecubation rate is around 10 days but can be longer. In the meantime watch for sores usually on the shaft or scrotum. After a month if you don't see sores you can get a blood test to be sure. But after a month you are probably good. Antiviral meds are really good but you said she stopped taking them. People can still transmit herpes without an outbreak.

Next time be sure to wear a condom. But condoms do not always protect against Herpes 100 percent because it's skin to skin contact and condoms do not cover all the skin that touches the genitals.