Thanks for reaching out. Could you tell us the Nest device you have? What error message are you getting when trying to invite your spouse in the Google Home app? Also, make sure she's using her personal Gmail account. Keep us posted.
I appreciate the help, MplsCustomer.
Just checking in to make sure that you've seen our responses. Please let me know if you have other questions or concerns as I will be locking this in 24 hours if I won't hear back from you again. Feel free to start a new thread and we'll be happy to help.