I recently lent a friend A LOT of money with his verbal and written promise to pay me back. He’s now reneging on owing me anything.

If you loaned the money to the husband, with no loan to or guaranty from the wife, you have no claim against the wife ond the debt.  However, if you believe that assets titled in her name are really the husband's in whole or part, or if you believe that he made a fraudulent conveyance (see below) to her, you can go after those assets once you obtain a judgment against the husband.   A fraudulent conveyance is when a debtor transfers assets to someone else with the intent to keep those assets away from his creditors OR when a debtor who is involvent, or is rendered insolvent by the transfer, transfers assets to someone else for less than fair consideration (i.e. selling a car worth $20,000 for $12,000 would be an $8,000 fraudulent conveyance) and then can't pay his debts.