why do I always stay?
When I stayed it was due to:
1) fear of what would happen during divorce (also ignorance about divorce in general)
2) a sort of chronic long-shot hope that I could fix him, if only xyz
3) an unconscious preference to complain about him vs work on me
4) ignorance about emotions, what emotional health really was (for me and my son)
5) financial uncertainty, wondering if I was too old to meet someone else, future worries, etc.
It's a bit of a hero's journey to divorce a person with severe pathology. You have to grow.
And that's often painful.