Narcissistic abuse is not consistent and it tends to happen in cycles getting increasingly worse over time. It's subtle, often covert, and insidious in nature. When a narcissist may be having a secret affair or even living an entire secret life (as some of them do) they will most likely act extremely happy with their relationship (usually because they are) and make out to their partner that everything is better than ever.
They will make their partner feel comfortable and they will make the
effort to make the relationship work. Technically, for the narcissist,
things are better than ever - the victim is allowing them to get away
with their lies, abuse and cheating and the narcissist is successfully
doing so. However, should the victim start to question the narcissist
about any of their suspicions then this is when the abuse is likely to
start once again.
The narcissist will start acting the victim once again, making out that
they are sick and tired of such accusations and probably that the victim
is paranoid and being abusive again. The narcissist will then proceed
to destroy the victim's reputation by setting up a distortion campaign
and spreading malicious lies and rumours mixed with negative truths
about them behind their back, should the victim keep on pushing.
The victim will be deemed the crazy one unless they just shut up and let
the narcissist carry on with their secret lies, abuse and sordid
affairs indefinitely. The pattern is repeated throughout the entire
relationship (the narcissist's dance).
[ Image from WikiMedia Commons - Public Domain - http://en.wikipedia.org/wiki/Narcissism#/media/File:Narcissus-Caravaggio_%281594-96%29_edited.jpg ]