Suspicions between husbands and wives will...,

[Silverobama]

Which of the translation is natural to native speakers' ears?

a) Suspicions between husbands and wives will impair the quality of their marriage.
b) Suspicion between husbands and wives will impair the quality of their marriage.

The context is if husband and wife (husband and wife in general so I use the plural) suspect each other (more than once) this will harm the quality of the marriage.

If it's not natural, could you please provide me a natural version?

 

[Rover_KE]

Only 'suspicion' is natural.

It would also be more natural if you changed 'husbands and wives' to 'couples' and 'marriage' to 'relationship'.