Sforno on Genesis 38:12/ספורנו על בראשית ל״ח:י״ב

1ותמת בת שוע, so that Yehudah should have brought his daughter-in-law into his house as a replacement for his wife. This is what Avraham had done when Yitzchok’s wife Rivkah moved into Sarah’s tent after the latter had died. (24,67) Yehudah’s failure to give Tamar his wife’s quarters to live in may have caused her to despair of having any kind of future in his family.