Sforno on Genesis 35:8/ספורנו על בראשית ל״ה:ח׳

1אלון בכות. Mourning results in the withdrawal of the Divine Presence as we know from Shabbat 30. Until Yaakov had passed this tree after mourning Deborah the Divine Presence did not return and accompany him. [He was deprived of such a Presence during all the 22 years that he was mourning for his son Joseph, thinking him dead. Ed.].