If a lady should stay with a cheating man, there are many things involved:

1) She's not faithful herself

2) Some benefits she's enjoying from the man and can't afford to lose

3) She might have some dangerous plans to nail him down. The man should be very careful. She might be planning a grievous revenge.

4) She doesn't know where to start from if she leaves the man i.e she gat no other options and she depends solely on him especially if there are kids involved etc. She might have also over invested herself in the relationship.

5) Societal discrimination: In a bid to avoid being the subject of gossip and unpleasant reference among friends, colleagues, family members, neighbours and even siblings, some women have had to put up with cheating husbands. She might also stay put in order to avoid being blamed for the failure of the marriage.

Or simply, the man have money