Welcome-
I wasn't married to a narcissist, but I was in a relationship with one for 15 years and I'm still trying to get everything separated. We have a four year old daughter together and she is what finally gave me the courage to leave.
I don't know your situation so I don't feel comfortable giving relationship advise, but it took me a long time to realize that my gut feelings weren't wrong. I should have been following them from the beginning and it could have saved me a lot of heart ache. But then, I wouldn't have my daughter. There's a book I started reading when I was really serious about ending the relationship called "Splitting" by Randi Kregor about divorcing someone with borderline or narcissistic personality disorder (my ex has both). It helped guide me through the bs and made me realize what games were being played and what the best response was.
Feel free to message me if you have any questions. No matter what happens, I wish all the best to you and your children.