A spouse can NEVER be claimed as a dependent ... you either file a joint return or not.
Prior to 2018 there was an option to file separately and claim the spouse's exemption (NOT claim them as a dependent ... similar but different) but since the stimulus payment is based on the 2018 or 2019 return this is immaterial.
So if you did not file a joint return you should be getting a stimulus check direct deposited if you receive SSI or SSDI.
