Does Facebook have a way to target the spouse of someone who meets certain demographic/interest criteria? For example, could you target an ad to spouses of firefighters or spouses of teachers?
No, there is no direct way. There are seven ways to target an audience:
- Custom Audiences
- Age & Gender
In your case you can use Custom Audiences option. For this You should know all the firefighters' and teachers' spouse Facebook ID or email address or username.
You can try Demographics/Interests also but it will target all the people.