How do I change my relationship status on Facebook?
To add or edit your relationship status:
  1. From your News Feed, click your name in the top left.
  2. Click About, then Family and Relationships in the left column.
  3. Click Add your relationship status or hover over your relationship and click Edit.
  4. Choose your relationship status from the dropdown menu. Depending on your status, you may also have the option to add the name of the person you're in a relationship with and your anniversary.
  5. Use the audience selector to choose who you want to share this with.
  6. Click Save Changes.
You can also add your relationship status as a life event on your profile.
Note: You can only list someone in your relationship status if you're friends with that person. That person also needs to confirm that you're in a relationship together before they're listed in your relationship status.