(א) וַיֹּ֧סֶף אַבְרָהָ֛ם וַיִּקַּ֥ח אִשָּׁ֖ה וּשְׁמָ֥הּ קְטוּרָֽה׃
Rava said to him: ...It is written: “And Isaac brought her into his mother Sarah’s tent, and took Rebekah, and she became his wife; and he loved her, and Isaac was comforted for his mother” (Genesis 24:67). And it is written immediately afterward: “And Abraham took another wife, and her name was Keturah” (Genesis 25:1). After seeing his son marry, Abraham was disquieted by the fact he was not married. This is akin to one who sees another eating and does not eat.
§ Rabbi Yehoshua says: If a man married a woman in his youth, and she passed away, he should marry another woman in his old age. If he had children in his youth, he should have more children in his old age, as it is stated: “In the morning sow your seed, and in the evening do not withhold your hand; for you do not know which shall prosper, whether this or that, or whether they both alike shall be good”ץ
The Gemara asks: Is that so that a man is matched to a woman according to his actions? But Rav Yehuda says that Rav says: Forty days before an embryo is formed a Divine Voice issues forth and says: The daughter of so-and-so is destined to marry so-and-so; such and such a house is destined to be inhabited by so-and-so; such and such a field is destined to be farmed by so-and-so. This clearly states that these matters, including marriage, are decreed for a person even before he is formed. The Gemara answers: This is not difficult. This statement that Rav Yehuda says in the name of Rav is with regard to a first match [zivug], while this statement of Rabba bar bar Ḥana in the name of Rabbi Yoḥanan is with regard to a second match. A first match is decreed in heaven; a second match is according to one’s actions.
זוג שני - לפי מעשיו וקשה לזווגן לפי שאינה בת זוגו:
Because of his deeds, and it's harder to find the perfect match because it isn't divinely ordained.
(1) When a man takes a wife and consummates the relationship, if she fails to please him because he finds something obnoxious about her, he may write her a bill of divorce, hand it to her, and send her away from his house;
Second Time’s the Charm: in praise of second marriages
By Mindy Leaf
Yet he admitted that a big reason for the success of this second marriage (other than obvious maturity and knowing a bit more about who he was before choosing a life partner—something no 21-year-old is likely to achieve) was his negative experience with his first union. After years of therapy (which his ex-wife suffered through and his next wife, me, benefited from!), he'd become a changed man. And so right off the bat, coming into his second marriage, he was able to be a far better husband, and then father, than he'd been during his first go round. I don't feel guilty about reaping the rewards of his former failure, as it was his ex's decision to call it quits after twenty years. It seemed, no matter how hard they tried, they would never be right for each other. Even their marriage counselor, after countless sessions, finally dismissed them saying he'd never met a more incompatible pair.