How did I lose my best friend of almost 20 years because her (new & only) baby daddy is an ass?

Seriously... I LOST my best friend. We have been BFF's for almost 20 years. She just had a baby with this uneducated ass who judges everyone he comes in contact with. He is rude and condescending, and I have pleasantly tolerated him since they have been together. I have always kept my opinion of him to myself and have never let on about how I really felt about him because I love my BF and I would never want her to be unhappy. They guy makes her happy and he is good for her, but he is a jerk to everyone else. Long story short he made some rude remarks to me in front of my child. I answered back out of rage (which is very uncommon for me). I believe he pushed me over the edge, and I had a moment of insanity. When I gently brought it up weeks later my BFF tried to psychoanalyze me - that's how she is) and tried to text book over-rationalize her mans behavior, eventually turning on me (too much tony robinson and life improvement courses). Anyway, the point is... I lost her. She apologized for the incident with a ridiculous legal jargon apology: "all parties have affirmed that his comments were inappropriate". What kind of friend apologizes that way? What kind of friend doesnt stick up for her best friend when it has been "affirmed" that he was a jerk? I used to talk to her every day. We have been through so much together. We have literally grown up together, and I feel lost now. How do I make amends?