There are a few details in your question that are worth clarifying - and those clarifications get at the larger answer to your question. I want to start by offering some quick history about the institution of chattel slavery as it's necessary context for understanding the relationship between white women enslavers and the Black women they and their family enslaved. I'm coming at your question from my understanding of the history of white women in America as well as the history of childbirth and abortion and as such, someone may offer a different answer if they approach your question in a different way.

The first thing to clarify is that importing people from Africa or the Caribbean for the purpose of enslavement in the United States ended when the "Act Prohibiting the Importation of Slaves" went into effect in 1808. Prior to that though, beginning in the late 1600s, English colonies established the concept of partus sequitur ventrem or "that which is born follows the womb" which meant that every child born to an enslaved woman was legally born into slavery - regardless of the child's father's legal status. Finally, historical demographer J. David Hacker wrote, "all researchers have agreed that slave birth rates in the nineteenth century were very high, near a biological maximum for a human population" in a study of slave birth rates between 1619 and The Civil War. This statement helps us better understand that when enslavers sought out enslaved women and girls for the purpose of reproduction, they didn't see them as their "mistress", which implies a sense of active participation by the enslaved person. Instead, the primary driver for such interactions was the creation of children who would be born into slavery. This is not to say there were never instances where an enslaved woman experienced pleasure from a sexual relationship with her enslaver or there was zero agency on her behalf. We do, though, have to be careful we don't inadvertently advocate the idea it was the norm.

So, what language or words do we use instead? ("Sex slave" works to a certain extent, but the enslaved women and girls had other responsibilities beyond procreation and were full, complete people deserving of language that goes beyond the worst things they experienced.) In a longer answer about the relationship between white women enslavers and enslaved people who could get pregnant, /u/Georgy_K_Zhukov offers:

Before we continue, a word on definitions. Rape is a term that can be applied to essentially any sexual relationship between an enslaved person and their master. The practical forms which master-slave sexual relations took ran the gamut from brutal and forced submission to 'real' relationships, but it cannot be separated from the framework in which they occurred, namely the actual legal ownership of the enslaved woman and rights to her body. No matter how willfully a slave-woman (or man) acquiesced to a sexual relationship, their consent within that framework cannot be entirely separated from the fact that the consent was not required, and was given with that understanding. It is a balancing act, really, as we both don't want to overlook the systemic framework in which the sexual relationship occured, but as the same time in looking at it broadly, we musn't deny the agency of some slave women who, within that framework, nevertheless did at times have some choice, however limited. Put another way, if asked "Was it always rape?" the answer is "Yes, but no, but yes": The power-dynamic intrinsically places it within that framework; but we shouldn't deny the women agency; but we then shouldn't overcorrect and let that agency trump the fact that they had no choice to be within the system which gave them the limited choices they did have. On a macro level, yes, it was always rape, but that shouldn't stop us from seeking to understand the intricacies and realities of the actual lived experiences of those enslaved women (and men).

The whole post does a great job getting at white women enslavers' thinking about such relationships or interactions. Which leads to the second detail in your question worth unpacking. If you want to share more about where you heard/read that white women were jealous, I'm happy to look at it but this idea that a white woman enslaver would be jealous and would deliberately mutilate an enslaved woman or girl she owned doesn't really fit with the historical record as I understand it.

One reason it doesn't really make sense is that in many instances, enslaved women or girls who gave birth on a farm or planation played a role in the health and well-being of white children born to the enslaver, especially as it related to breastfeeding. I'll quote an older answer of mine:

The relationship between enslaved women and girls and white woman and their infants varied dramatically between plantations and communities. For every enslaver who forced enslaved women to feed infants that weren't their own, including the enslaver's own children, there were enslavers who felt white babies would be harmed by being fed by an enslaved woman. Meanwhile, there were white women enslavers who routinely fed enslaved babies who needed more milk than their mother could provide and others who handed their babies off to an enslaved woman, indentured servant, or paid wetnurse for feedings as soon as the baby was born.

In other words, it was not uncommon for a white woman enslaver to need the help of an enslaved woman who'd recently given birth to keep her own child alive. At the same time, physical punishments to an otherwise healthy enslaved person who could get pregnant ran contrary to the idea of chattel slavery. (I get into that a little bit more in this answer about how enslavers raised their children to be enslavers.)

Which leads us to the matter of how enslaved women and girls who were raped by their enslavers were treated by other enslaved people. The straightforward answer is that it depended on a number of factors. We know that enslaved women and girls who recently gave birth did practice a form of communal child-rearing, with older children who were too young to work tasked with watching over the babies and infants. There are also first-hand accounts that, on some plantations, breastfeeding enslaved people were called out of the fields at the same time, as a group - regardless of their babies' needs - to breastfeed, in order to make it easier to supervise their movements. We know of instances where women and girls who recently gave birth to a child fathered by their enslaver ended their child's life and were provided assistance by other enslaved people. Finally, we know of instances where enslaved women killed the white children of the enslaver and were helped to escape by enslaved men. (Ramey Berry and Gross' "A Black Women's History of the United States" gets into these histories, especially in Chapters 2 and 3.)

So, all in all, it's pretty safe to say that how a community of enslaved people felt about an enslaved women or girl who'd been selected as a way to increase their enslavers' slave population was complex, contextual, and dependent on the type of community the enslaved people were able to create.