You must tell your partner you have genital herpes. If you pick the right time and say it the right way, there's a good chance things will work out OK.
Think about how you want your partner to take the news. Do you want it to seem like a huge problem? Of course not, so don't present it that way. If you say, "I have some awful news for you," your partner will likely take it as awful news. Instead, be casual, direct, and unemotional.
Also avoid suggesting how they should react, especially in the negative. If you say, "You're going to freak out when you hear this," or "Don't freak out, but...," you are setting your partner up to panic either way.
Simply say you have genital herpes, and ask if they know what that means. Be prepared to present the facts.
Learn as Much as You Can About Genital Herpes First
Before you tell, learn all you can about genital herpes so you can be prepared to answer any questions your partner may have. Stress that it's very common. Hearing the one-in-five statistic could be a relief. Also explain what it means to have it. Some people get sores on their genitals occasionally, but many others get symptoms so mild they don't even notice them.
Choose words wisely. You don't want to load the discussion with negative imagery. Although genital herpes is a disease, saying that you have this "disease" conjures up unpleasant images, so avoid using that word. Watch adjectives, too. Don't describe your condition as "horrible," "disgusting," or "incurable."
Pick the Right Setting
In addition to language, the setting can affect the outcome, too. Don't interrupt what your partner is doing to break the news. That is, don't call them at work, or barge into a room and say, "Hey, we have to talk." That's how you might deliver news of a death in the family or start an argument.
The right setting is a relaxing one, just the two of you, where there won't be any distractions. A conversation over a quiet dinner or a walk in the park is preferable to a bowling alley or the supermarket.
The worst time to tell, other than after having sex, is during foreplay or when your clothes are already off. That would not only spoil the mood, but it could also annoy your partner.
It is usually best to let the topic come up naturally in conversation. That way, it will seem less like a bombshell and more like any other development in your life. For example, you could say, "Just so you know, my doctor called me yesterday with some test results, and said I have the virus that causes genital herpes."
If you've never slept with the person before, it's not impolite to ask if they have any sexually transmitted diseases. You could start the conversation by being the first one to ask. It's possible that they might start giving you the same herpes information you had been preparing to give.
It's also possible that your partner might take the news badly no matter how well you deliver it. In that case, don't get defensive. Allow them some time to think it over in private, calm down, and come to terms with it. It may not be the first challenge you've faced together, and if the relationship is valuable enough to continue, it won't be the last.