I would stick with the job.
I felt in the same boat when my kids were small. I spent years deliberating - I tortured myself. Everyone advised me to quit my job. I did actually quit a couple of times when it got too much, and regrettably I did have to take time off sick sometimes.
No doubt I will get grief for this, but I stuck with it out of principle, because I could not bear to give in to the "patriarchy". It's not a conspiracy, but I feel we as women will never be equal until we are prepared to stick with it. I feel we have to lead the way somehow, not just for us but for our daughters, and for women all over the world who do t have those opportunities.
In terms of my kids, they were okay. They are now academically successful, independent teenagers.
The only real sacrifices in retrospect were the ones I made in terms of exhaustion and effort, plus missing time with them. Having said that, excess time with them can be too much anyway. But then I just felt lucky when I pictured all the brave women like single mums who work to the bone for less reward.
Now the kids are older, I've ticked all my career boxes. We are comfortably off, we have a lovely house, and I have a decent pension for the future. I am now taking some time off for study and possibly a change of direction.
I've set a good example to my daughters and they never once question my decisions.
Too often, we encourage women to give up. I had so many people telling me to put "life" first over work. But in my view, you never get anywhere without hard work. I like to feel the stretch.