The first question is whether wife truly is the sole owner. She may not be, even though the house is "in wife's name."
But let's pretend that wife is the home's sole owner. The next question is whether husband is a tenant. Only a lawyer can tell you for sure. If husband qualifies as a tenant, wife must follow all of the rules in the Oregon Landlord-Tenant Act if she wants to kick her husband out.
If husband does not qualify as tenant, this would be something that divorce court could help with, if your separation goes that far. Otherwise, you may need to file a lawsuit against him for ejectment.