Matthew 1:19

19 Because Joseph her husband was faithful to the law, and yeta did not want to expose her to public disgrace, he had in mind to divorce her quietly.

Read Matthew 1:19 Using Other Translations

Then Joseph her husband, being a just man, and not willing to make her a publick example, was minded to put her away privily.
And her husband Joseph, being a just man and unwilling to put her to shame, resolved to divorce her quietly.
Joseph, her fiancé, was a good man and did not want to disgrace her publicly, so he decided to break the engagement quietly.