My (35M) wife (34F) hid her mother’s mental disorder for 10+ years

My wife and I have been together for 10+ years. Since before we met, she has been aware that her mother has been diagnosed with schizophrenia. We have 2 kids, 3yo and 1yo. My wife has been hiding that her mother has schizophrenia until few days ago, when my wife was emotionally vulnerable and decided to share it with me. I reacted with empathy, because I needed some time to think about it.

From one hand, I understand how difficult it must has been to bare such a heavy weight because she basically had to take care of her mum in her late teens. From the other hand, I feel betrayed because she hid it for so long, and the only reason she shared it with me was because she is not emotionally stable right now (partly due to how her mum treats her).

I have gone so far as to even contemplate divorce (obviously there is more to the story), and this is something that I really do not want to do because I am scared that I will obviously lose the kids (for me, not living with them = losing them).

For the last 1-2 years I have been full time working, taking care of our child + pregnant wife (then of the baby after birth and of my wife due to some complications), cleaning the house, doing renovations, cooking. I sound an asshole, but my life would actually be much easier to raise the children by myself as this point.

The situation is obviously more complicated than what I wrote above. My wife and I love each other and wish the best to one another. I am lost. How do you feel reading this? I am happy to answer any questions.