This is a very difficult and emotionally draining situation. I have lots of empathy and I understand what you are going through.
I had a similar experience with my now ex. wife. I tried to help her for years and years, spent thousands on therapy, all the while explaining to her she appeared to be suffering from bipolar disorder and borderline personality disorder. She didn’t listen - carried on regardless, lied to every single last person, including the doctors and therapists. Spent £10,000s, abused me, multiple affairs. That’s the tip of the iceberg.
Our marriage finally broke down almost 4 years ago. 2 years ago she ended up being sectioned for 5 months and has been admitted multiple times since then. Guess what. Diagnosed with bipolar disorder and BPD……….
My advice to you is that there’s only so much you can do. You can lead the horse to water. But…… You must look after yourself and your own mental health and the kids. I didn’t look after myself very well and I’ve paid the price a bit now. You don’t realise it at the time, but all of these experiences do damage. It very nearly broke me.
Please look after yourself. You aren’t a super hero and you may not be able to help anymore. That isn’t you failing. It’s just the way it is sometimes.
You aren’t alone and others have experienced similar. You will get through it! Be bold. 😊😊