Parental alienation …

Today is my son’s 18th birthday. My ex has alienated me. I haven’t spoken to my son in nearly 4 years. This used to be such a happy day for me because it was the day I became a mommy, but now it just hurts worse than words can describe. Does a mother ever stop mourning? (Mourning in this case the death of my mother-son relationship) … I’m so sad.