Will no contact work on insecure ex?

My ex is very insecure . The first time we broke up , I massively texted and did things to win him back (sending letters etx) Though it resulted in him being very nasty to me , he eventually came back when he thought I had given up (and during this time he still msg me a few times) . This time we broke up again over the same issue, but due to previous experience I decide to do no contact as the I have phobia of the previous reactions from him . Am I doing right to maintain no contact or shd I keep assuring him I’m still willing to work things our ?

Keep No contact. It sounds like you both need to sort yourselves out first.