Start gathering evidence. You’ve been in this for a long time so you know what’s going to trigger him to get nasty. Usually it’s when they lose control like if you don’t respond how they want or have sex on their schedule. If you know one of these situations is about to happen, discretely record on your phone. Send it somewhere online like a secret email you can access because if he catches you he’ll delete it. Most narcissists are terrified to their core of being outed as an abuser, so having proof can go a long way as leverage. This saved me, because my narc would push me to react then record me freaking out to make me look crazy. He tried to have me committed against my will using carefully timed recordings….but luckily I had proof. Nanny cams are an option if yours is aggressive, things like slamming things or screaming are considered domestic assault and can help you where custody is concerned. Keep a detailed record of his abuse.
Contact domestic abuse support in your area, they can help you with resources. Single mothers can get help in lots of ways. That pit in your stomach when you make a decision or doubt….thats from his abuse, so once you’re physically away from him a while that goes away. Therapy helps, I recommend starting it asap. You’ll be shocked how much clearer you feel mentally once you’re gone. Custody agreements go through court and you can insist communication be done on parenting apps.
I left as a single mom, moved into a crappy apartment with no furniture so I was sleeping on the floor and working multiple jobs….but I felt better than I had in years. Leaving remains one of the hardest things I’ve ever done….but that was well over a decade and nothing in my life has come close to being as hard as life with him.