No. Twin flames never cheat. So if your twin flame cheats, that is because they are not, never were, twin flames.
In this manner, do twin flames ever end up together?
Many twin flames will end up making their way back to each other, even if it takes years—but not all. It depends on the level of work the twin flames do individually while they are separate. Some twin flame relationships can be toxic, however, and they may never reunite—or shouldn’t.
Correspondingly, will my Twin Flame leave his wife?
There is no guarantee that the TF will ever leave the marriage. People are usually married to Soulmates with life long pre-birth plan with the spouse and kids. If he is married to a Catalyst or Karmic – he might, these are temporary contracts.