Children exposed to even mild levels of tension between parents suffer.
Regardless of whether parents stay together or split, if there is fighting going on between them, the children will suffer.
Most "pro-marriage" factions will try to tell you that divorce hurts children. Judith Wallerstein did some of the greatest misleading in her research and subsequent book entitled, The Unexpected Legacy of Divorce.
Many people took her findings to heart that divorce harms children - not just in the short term but for many years to come. Without going into the obvious flaws that have already been exposed in her work, I will suffice it to say that any longitudinal study on families like this can't possibly yield accurate results because you have no way to compare these families to the alternative.
For example, you can't compare the same family getting divorced while also not getting divorced. The closest you can come is to compare a family who divorces and another family who stays in tact. There are a billion factors (OK, perhaps a slight exaggeration) that distinguish these families such as culture(s), ages of children, socio-economic status, degree of tension in the home, and on and on.
There are some interesting and surprising studies out that show even small amounts of parental conflict can cause problems for their children. I've included a link below outlining these results:
http://news.healingwell.com/index.php?p=news1&id=530961
In addition, Robert Emery, PhD, who wrote, The Truth About Children and Divorce, does an excellent job of coming in from the two extremist views about whether divorce does or doesn't harm children and says the truth is somewhere in the middle. He goes on to say that, in cases where the parents do argue often, divorce can actually be a relief to the children because they no longer have to live with all the tension they had experienced.
Every situation is truly unique and a myriad of factors need to be weighed such as timing, age of your children, safety for you and your children, financial ability to split up as well as other resources on hand.
Here are some questions to ponder that may make it clearer whether your children would benefit from parents staying together or separating:
1. What is being modeled for the children about marriage and relationships?
2. What impact (positive and negative) would parents living apart have on the children? Consider the child's temperament, age, your finances, health, safety, and resources.
3. As the one contemplating divorce, picture yourself still married in five years. How does that make you feel?
4. Try committing yourself fully to the marriage for 6 months and see how that feels. What new information do you get as a result about whether or not to stay?
5. If you are staying in an unhealthy marriage for the kids, take some steps to separate temporarily and see what happens.
These last three questions are designed to have you step out of the indecision into a decision one way or the other. When people are stuck in the confusion, it has a snarling effect and it becomes increasingly difficult to get clear on what to do.
It's important to get a reprieve from this place in order to uncover what the next right thing is. Staying for the children can seem like "the only right thing to do," but it is not in all cases.
Children are resilient and when you are happy, they are much more likely to be happy.
Source: https://www.psychologytoday.com/gb/blog/contemplating-divorce/200911/divorce-doesnt-harm-children-parents-fighting-harms-child