What does attorney-client privilege mean exactly? It means that when you seek legal advice of any kind from an attorney, that attorney is forbidden from communicating to anyone what you tell them in confidence. So even if you tell your lawyer where a body is buried, they are legally and ethically bound to keep that a secret.
In this case, it can seem like the ethics are backwards. If a lawyer knows something important to a criminal investigation, shouldn’t they tell the police immediately? Many lawyers find themselves in this very difficult position. But revealing a client’s secrets would break the important bond of trust that is necessary to provide fair legal counsel to everyone.
Ethically, lawyers know they must keep their client’s confessions under lock and key, much like a priest knows they must keep their parishioner’s confessions under lock and key. Also, if a lawyer were to give up a client’s secrets they would face severe disciplinary action, including having their law license revoked.
Since you take no risk in doing so, you should tell your lawyer everything. Telling your legal counsel the whole story will help them provide you with the most accurate professional advice and proceed in the best way without being blindsided in the courtroom with a fact that you failed to mention.
Going to a lawyer is like going to a doctor. You wouldn’t omit a fact from your doctor because it embarrassed you. Your doctor needs to know everything that’s going on, so they can treat you accordingly. The same goes for your lawyer. You can trust your lawyer. You risk more in telling them too little than in telling them too much.