Changing Account/Contact Name and historical billing/CR documents

*crowdsourcing and getting ideas*

When your Contact (client) needs to change their name in the middle of a billing period, maybe because they got married/divorce, and they had historical billing or payments that had their prior name, would you change the name in Salesforce/Accounting Seed and use their current name or keep the old name and add a new field in Salesforce to reflect their new name?