Welcome
Is your husband aware of the boundary you set? Having someone to help you enforce your boundaries can be really helpful.
I went NC with my mother a couple months ago, and it was mentally exhausting when my phone would go off. I silenced my phone and gave it to my boyfriend. Eventually I just had to block her. It was such a relief not worrying about what might show up on my phone.
If it makes sense for you, having your husband not pass along the information that she called in the future.