Hi Maniac. I don't know whether his rudeness can be backed up with legal talk. Stepdad seems to be taking some sort of responsibility for having a go at you. I don't know the dynamics of this family, but is there any issue about his control in this relationship?
I used to get nasty, abusive texts from ex-DIL and they all seemed to be her way of firing off some bullets to see how many people she could hurt. Nothing to do with what anyone might have done themselves - she just felt like it. She certainly threatened a lot that, in the end, didn't come to fruition. She emailed me within a week of the separation, telling me that her way was to jettison previous in-laws and have nothing more to do with them, and that's what she expected to happen in my case (conveniently forgetting I have a grandson!) I didn't rise to it, and waited patiently for the court to sort out what would happen, and they did. I now see grandson, as you know.
If there is a formal court order stating what contact channels should be, that is one thing, but if you are just a loving grandmother trying to keep in touch with your grandson, and no court has made a restraining order, or specific contact arrangement, then I wonder what stepdad is up to? Is he just trying to wipe you from the family and put fresh faces in place? Grandchildren have the right to know their place in their family, and these things can be managed when the children are put first. I hope this can be resolved for you Maniac. What a rotten time you've been having with your attempts to see your grandson 