2,257. Fraternizing With an Ex-Spouse

Hilchos Issurei Biah 21:26

A man is not allowed to go without a wife. One should marry a woman who is able to bear children. A woman is not obligated to marry, or she may marry a man who is impotent. A young man shouldn’t marry an old woman, nor should an old man marry a young woman, as this leads to promiscuity.

Hilchos Issurei Biah 21:27

If a man divorces his wife after marriage (as opposed to after betrothal), he may not live in the same courtyard as her as this may lead to promiscuity. If he was a kohein, he may not live even in the same alley as her. A small village is the same as an alley. If he owes her money, she should assign an agent to collect from him. If a divorced couple both come to court, they are placed under a ban of excommunication or given stripes for acting rebelliously (because they’re not supposed to be together). However, if a woman is divorced from betrothal, she may call him to court and may live near him. Excessive familiarity, however, is prohibited even after betrothal. In such a case, the woman is the one who has to move unless she owns the courtyard, in which case the man must move.