The suttas are mostly (not all) by and for monks, less detailed on the subject of married life and so on.
Buddhism & Divorce implies there's not a lot of explicit doctrine on the subject -- perhaps little more than that "lay life is confining and a dusty path".
You might be interested in a book The Buddha's Teachings to Laypeople: Practical Advice for Prosperity and Lasting Happiness. from which I summarised this answer -- it's based on the author's finding suttas that are relevant to lay life -- unfortunately I don't own a copy so I can't tell you now what it says about children.
This article -- A Happy Married Life -- might be helpful. It includes a section "Parental Responsibilities" (I'd suggest you read first only the first sentence of each paragraph to get an overview).
Again I imagine that the situations vary and that you could use some proper (personal, in-person and perhaps professional) counsel.
When I tried to answer your question What's the advice for dealing with an abusive partner? I did so without considering that there might be children involved, in the house. In my limited personal experience I think that children are better with one parent who loves them than with two who don't, and personally I always imagined that if I were a parent myself then I might be less willing and less able (because it would be less moral, less dutiful) to tolerate (condone, perpetuate) an abusive or less-than-ideal partner, even or especially "for the children".
But this is me describing or generalising from my personal experience, not yours -- so for that and other reasons I suggest you find a counsellor to discuss this with. Like if you were ill you should probably talk with a doctor in person, not self-diagnose nor read a book of pharmacology.