Tamar is now righteous

Genesis 38:25 says, “When she was brought forth, she sent to her father in law, saying, By the man, whose these are, am I with child: and she said, Discern, I pray thee, whose are these, the signet, and bracelets, and staff.

38:26 And Judah acknowledged them, and said, She hath been more righteous than I; because that I gave her not to Shelah my son. And he knew her again no more.”  When Judah first heard about Tamar he wanted to burn the harlot, now that she showed him the trinkets he had given her he calls her righteous?  She knowingly slept with her husband’s father.  That, my friend is a big yuck!  Should either of them righteous?  Does god think they are righteous?  Should anyone in this book be righteous?