Hi there -
No, kissing is fine. Just make sure to wait to have sex for 7 days after he gets treated.
And you might not get other stds from him if he has them. Herpes, for example, has a 10% chance of transmission per year from an infected male to a negative female.
You both should test for all stds.
Oh and the nurse is right - in 7 days, you are cured.