And especially don't wait until after you've had sex, which will only get the issues tangled up in emotions and distrust. Give him time to think about it. You may think that this should be easy to handle for someone who is not infected, but he has to weigh the risks of going through exactly what you did. Deciding to take a risk is not easy for a lot of people. If the reaction is negative, you are not to blame.
Most people respond well to the news.
In fact, with the alarming rates of STDs in the United States, there's a reasonable chance that he's already heard a similar disclosure. This is a difficult concept for many people, and it still hurts if someone rejects the risk you pose. But remember, you are far from alone. They can send you pamphlets on various STDs. They also operate a Herpes Resource Center with ties to over 100 local self help groups for people living with herpes, and they maintain a herpes hotline.