Most Helpful Guy
Most Helpful Girl
If you were the one to break up with him, then he has every right to follow your lead and excuse you from every aspect of his life. People who have been dumped tend to find liberation and peace in completely removing the dumper from their hearts, minds, and view in every way. The act of being left can cause a lot of heartache and distress so leaving that person in hindsight and committing to that choice by not including or inviting them into your life with social media can feel like overcoming an obstacle.
If not, then seeing as he now has a wife with children, he probably just sees no reason to keep you invited and included into his world at all. He has chosen to build his life around another woman; there's really no need to have you around mentally at all anymore.