http://revach.net/article.php?id=2192

Section: Parshas HaShavua   Category: Quick Vort
Parshas Emor: Kohanim and Divorcees
"They shall not marry a woman who has been divorced by her husband." The Shach explains the reason why a Kohen may not marry a divorced woman. He says that a Kohen symbolizes unity. He brings Klal Yisrael close to Hashem. Aaron was Ohaiv Shalom V' Rodef Shalom. Therefore, he should not marry a woman that went through a process of Pirud - separation. When a woman gets divorced, not only is there separation on this world; the couple's souls are separated in Shamayim, too.