As I understand it, you had your IRA custodian make a distribution from *your* IRA and transfer the money to *your* HSA, yet you are not eligible for an HSA contribution because you are covered under Medicare. That makes the IRA distribution taxable and the contribution to your HSA an excess contribution.
Assuming I understand correctly, you'll need to obtain a return of excess contribution from the HSA before the due date of your 2018 tax return. You can then make a contribution to your spouse's HSA (opening one if your spouse does not already have one) and deduct it on Schedule 1 line 25, offsetting the taxable income from the IRA distribution. However, if your spouse had self-only HDHP coverage, $4,500 is over the $4,450 limit for 2018 for someone over age 55, so only $4,450 can be contributed to your spouse's HSA.
