What can slavery do to the white people who own slaves? what about slaves?

I'm going to follow up on my last answer here. Slavery was dehumanizing to both slave holders and slaves. Many owners abused their slaves physically, mentally, and sexually. Slave women often became concubines to their masters, bore their children, and thus incurred the wrath of their mistresses. The offspring of these relationships (mulatto children) were often torn from their mothers and sold at the mistress' behest because they were in fact a symbol of their husbands marital infidelity. Mistresses would have found it difficult to have these constant reminders remain in their homes or on their property.

Slaves are hooked and whipped for infractions, they're murdered and forgotten ("it is worth a half-cent to kill a slave and a half-cent to bury one"), and they're often forced to steal in order to survive. Slaves considered "too" difficult (this could be defined as spirited) are sent away to be broken by the cruelest of taskmasters (think Mr. Covey).