Wife of Bath

In the prologue of the Wife of Bath, she tells of her fourth husband's funeral. She goes on to say that they get married a month after her previous husband was buried in the grave

In this time period, weren't there social rules which forced the lady to mourn for a certain period of time? And even if she did disregard the customs, would a respectable clerk, who hates women, agree to re-marry the Wife of Bath so quickly after the death of her fourth husband? It seems very unrealistic to me.