First, while we assume that all of the Chachmei ha'Mishnah vha'Gemara were Tzadikim, it is not clear that we must assume the same for their wives. We find, for example, that the wife of Rebbi Chiya made life difficult (Metza'er) for him (Yevamos 63a).

But even assuming that the wives of the Chachamim were punctilious in their practice of Halachah, perhaps Rebbi Avahu's wife's behaviour was not out of line. Perhaps she was concerned that her husband's continued relationship with the Meturgaman would damage his reputation. If the Meturgaman's wife was telling even Rebbi Avahu's own wife what the Meturgaman thought of him, then presumably she was sharing it with others as well. In other words Rebbi Avahu's wife's intention in telling him was l'To'eles, to protect him from slander (see Chafetz Chaim, Hilchos Rechilus, ch. 9).

Kol Tuv,

Yonasan Sigler

This is not a Psak Halachah