Perpetrator

No bones decayed, no flesh began to rot
Her body's been preserved, in her sopping crypt

38 years she's been entombed, after a sudden illness
A tonic has preserved her corpse and now restored her life

Back into the arms, of the man she was to wed,
Because of this union she initially wound up dead

She gave her heart to another man, best friend of her beloved
Yet could not bare to despair, her lover with the truth
She went against her urge, give to him her hand
His friend in grief he poisoned her, which led to her demise

Her life now revived, her lover has rejoiced
But in truth has been confessed, he now detests his friend
In arms against each other, it ends with the lover dead
The tonic drained, deterioration devoured this woman's corpse
The friend now left alone, he has lost the ones he's loved
For the life he took years ago, he received his punishment