Check who should receive the message
Confirm that you have the right person, the right role, and permission to disclose the information involved. For a message about how to decline a wedding invitation respectfully, use this factual base: acknowledge what was requested, any real timing issue, and whether your answer applies only now or more broadly.
Separate information from interpretation
Label confirmed facts, open questions, and the specific decision that belongs to the recipient. Give a direct no, a limited alternative only if you mean it, and any practical information they still need. Make the immediate next step clear enough that the recipient can answer without reconstructing the entire history.
Use formal help when stakes rise
Do not overexplain private details, blame another person, or say maybe when the answer is no. When pressure, coercion, or retaliation is possible, use a safer channel and involve appropriate support. Medical, legal, financial, employment, and safety decisions may require a qualified professional rather than personal persuasion.