I get "well that's good, did you get an apology"
My mother was raised by an alcoholic mother who's alcoholic boyfriend not only beat my grandmother but also beat and abused my mother as well.
Do you think that perhaps that she's subconsciously a bit jealous and is actually living vicariously through you? That apology is something that she perhaps wished for as well. Not that she would ever admit it.
The other thing that struck me... your mom called you at work. My mom NEVER calls me at work unless it's an emergency. My parents learned their lesson a long time ago when they called me at my cubicle for the umpteenth time and I finally lost it - the person next to me started clapping and they heard it!