You have to tread carefully on NC because it can signal different message than the intended one. He might think you've ghosted him - ended the relationship without telling him - or you're in a relationship with another person.
Another thing is that he might ignore you because as you've said, he always does things his way and has been taking you for granted.
What should you do? You should address the situation. Let him know how you feel and that you feel he's taking you for granted.
If he doesn't take into account how you feel, you should exercise NC indefinitely until he makes the first contact.
If he doesn't consider or respect your concern, you'll always end up being hurt. This will prove catastrophic when you start staying together.
He will know your worth when you employ NC after realizing you told him but he didn't pay attention thereby you resorted to remaining silent.
If he doesn't contact you during NC period, don't contact him. You will realize then if he is the man you would want to spend the rest of your life with.