The dreaded moment in every relationship would be when you each decide to be honest with each other. And by honest we're not talking about how many exes your boyfriend had, or how he lied to his parents about being a virgin at 25. We're talking about deal-breakers here. Stuff that will send your phones flying across the room and send your palm to his cheek with a clean, crisp slap.

Here are some experts' tips to dealing with the dirty surprises with calmness and patience. Learn how to talk to a man after he reveals that he:

…has herpes:

This may not necessarily be a deal-breaker. "When people hear STD, they think promiscuous," says Carole Marks, M.D., associate director of the department of family medicine at Long Island College Hospital in Brooklyn. "But just one bad decision can lead to a lifetime of painful breakouts."

You may get angry that he's held out on you, but bear in mind that he's announcing his STD to try to save you from being exposed. And confessing an STD secret is not easy. "He's probably terrified that you'll reject him," says marriage and family therapist Bethany Marshall, Ph.D., author of Deal Breakers: When to Work On a Relationship and When to Walk Away. "He's feeling vulnerable, embarrassed, and possibly even ashamed."

Don't command him to spill his entire sexual history, but ask him how and when the diagnosis was made and if he's been tested for other STDs. "Find out if he's on suppression therapy; Valtrex, a daily oral medication, in addition to using condoms, reduces the risk of transmission," Marks says. If he isn't, ask him to look into it for your sake. Be honest about how willing you are to risk getting the disease. "The fact that he has herpes is not necessarily a deal-breaker," Marshall says. "But you might want to delay having sex until you're sure the relationship is serious."

…wants to quit his job to "find himself"

"Ask him how he thinks this transitional phase will affect the relationship and how long he sees the transition lasting," says Nancy D. O'Reilly, Psy.D., a clinical psychologist based in Springfield, Missouri. "If he's vague about what he wants to achieve and how he plans to achieve it, be worried." Letting him seek a more fulfilled life doesn't mean giving him license to play with his Xbox 360 all day. He should be able to soul-search and pull his weight at the same time, whether that means doing chores or getting a part-time job.

If your combined income will drop significantly, "work together to create a practical plan for the immediate future that addresses your needs too," says Don Rosenthal, co-author of Learning to Love: From Conflict to Lasting Harmony. Plan a budget that shows how your household will operate on less money and avoid sacrifices you'll resent him for later.

…secretly withdrew money from your joint savings to buy a new flat-screen TV

Be clear. The issue here is secrecy, not money. "Call him on his sneakiness and unilateral decision-making, but don't be hostile," says Daniel L. Buccino, assistant professor of psychiatry and behavioral sciences at Johns Hopkins School of Medicine. Instead, express confusion. Start with this line: "Please help me understand what you were thinking when you spent our money without checking in with me." Move into an "I feel" statement, such as "I feel hurt and betrayed when you make big decisions without talking to me first"--and finish with your plan of action, Buccino advises.

To avoid a repetition of what happened, Scott Haltzman, M.D., co-author of The Secrets of Happily Married Women, suggests allotting half an hour every week to talk about financial goals for your shared accounts and how to use the funds. Another good idea would be to set up "yours," "mine," and "ours" bank accounts. "Adults need 'no-questions-asked' money of their own," says Liz Pulliam Weston, the author of Easy Money: How to Simplify Your Finances and Get What You Want Out of Life. For more expensive items, collaboration is still a must.

…changed his mind and doesn't want kids

"This is an instant deal-breaker," says Leah Klungness, Ph.D., a psychologist and co-author of The Complete Single Mother. "It's a clear message, and it's essential to understand that this likely is not negotiable." Changing his mind about his career, where to live, or where to vacation won't have life-altering consequences, Klungness says, but "children are the only 'always and forever' commitment."

If having kids is a must-have for you, hoping he'll magically come around to your point of view only sets you up for disappointment. Klungness adds that news like this involves an element of duplicity. "Perhaps what he's truly reconsidering is building a future with you," she says. "You deserve better than parenthood with a man who has been and may continue to be less than truthful."

…slept with his best female friend before he met you

Okay... But why is he telling you now? "Unless you asked for the declaration, this confession seems potentially cruel and hurtful; it doesn't help deepen or advance the current relationship," Buccino says - which is exactly what you should explain to him. If he can't explain logically why he felt compelled to confess at random, make cutthroat inquiries like: How long ago did it happen? Does he ever feel tempted to do it again? Does he or did he have deeper feelings for her--or anyone else? If you don't have a history of unfounded jealousy, use your gut to interpret his responses. Trust your feelings, and accept the truth, even if it's painful. By the end of it, you'll know where you stand - and whether that will be next to him.