What is the interpretation of a wife repeatedly seeing in a dream that her husband is cheating on her, and does this indicate that he is lying to her and hiding something from her?

The vision of a righteous believer is often truthful, but it may contain jumbled dreams, for only the visions of the prophets are entirely true.

A disliked vision may cause sadness, but the Prophet (peace and blessings be upon him) guided us to seek refuge in Allah from its evil and the evil of Satan, to spit three times, and not to speak of it, for it will not harm.

Satan is keen on causing discord between spouses, so it is not wise for a woman to make her life miserable with visions whose reality she does not know, or to search into her husband's past, or to confront him with what he has repented from.