Nagger. ( [sb] who nags) fastidioso, fastidiosa nm, nf. I know my wife can be a bit of a nagger, but she really means well.

Nagging is a natural response to that anxiety. To criticize or complain often in an annoying way, especially in order to try and make someone….
The First Is That It Takes Two:
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The First Is That It Takes Two:
Nitpicker, faultfinder, quibbler, objector, hypochondriac, pessimist, kicker, defeatist;
To Keep In A State Of Troubled Awareness Or Anxiety, As A Recurrent Pain Or Problem.
2 a horse that is inclined to stumble.
Neither The Nagger Nor The Nagged Is Fully To Blame.