derelict
disaffected
disloyal
disregardful
faithless
false
fickle
inattentive
inconstant
inobservant
negligent
nonadherent
noncompliant
nonconforming
nonobservant
not true to
of bad faith
perfidious
recreant
traitorous
treacherous
trothless
uncompliant
unconforming
unfaithful
unobservant
unsteadfast
untrue