How do you co-parent with a narcissist?

My boys are both so young. Supervised visits are coming to an end. How do you handle co-parenting with a narcasist. I worry their needs won't be met because he isnt even putting our 1.5 yr old down for a nap. How do you not worry, not care, and just go about your day??? Or even just coparent in general. Hes even starting to say stuff about me. Hes telling our son that im the reason he doesnt seem him as much. He's a recovery alcoholic as well.

Any advice. I have so much anxiety right now thinking about them being alone. Oe even supervised visits right now. Ik they deserve their father in their life but I cant get past all hes doing to make this more difficult. And yes we are in a custody battle.

Only adding here from comments because I dont want my name out there lol: he use to drink and drive with them both back in jan and feb when I didnt know he relapsed. So yes I worry because he hasn't lived alone in almost 10 yrs. He was in rehab. Lived with a friend after. Met me. We lived together . Then he went to rehab. Hes still in facility but volunteering there so hes not even on his own yet. He barely was there for the children when we were together. On one of his visitations he didnt even change a diaper. I came home to our son in a poopy diaper. He was emotionally abusive. And I see it happening with our children. He doesnt put them down for a nap and never has since the day they were born. He doesnt believe they need to nap. And he told me its not his job to put them down for nap. So i just worry about there well being.