we don't set boundaries in hopes that will teach THEM a lesson. our boundaries are not another's punishment.
someone in your life was being disrespectful to you.
as a measure of self respect, you enforced No Contact with this person.
the other person is under no obligation to respond, react or change to this new boundary. they are free to continue being however, you just don't have to deal with them.
your son may or may not change how he treats you.
meanwhile you can get busy living the same type of productive happy kind life you wish he would.