Setting a boundary is not being rude. Nobody proclaimed you a rude person. I hate to say this but I get the vibe that you sort of thrive on this drama with your H.
If the text is about the kids and not some other nonsense then by all means reply. Let ALL his calls go to voice mail. If the message is about the kids then call/text back. If its not then ignore for a while.
You seem to bypass the reality of it all - HE LEFT YOU therefore you will no longer be there to take his calls and listen to him talk about his day. That is a perk of marriage and he opted out.
I say this with a gentle tone but don't get wrapped up in a power struggle with your H. My H and I did that for YEARS and it will lead to nowhere but the demise of your marriage.
