SO = significant other.
I had a friend at school who was like the brother I never had. We were friends from the ages of 15 to around 27. We spent all our free time together. I made it through all of his relationships, including the one where his girlfriend had to get an abortion (we had a difference of opinion about that one - it turns out I'm pro-life when it's someone I know).
Then he met someone I didn't approve of. I felt that she was way too young for him (mentally speaking). Over time, we disagreed about her, and I referred to her directly as a child. Then when he said he was getting married, I reminded him of our agreement that I would be best man. He told me there would be no speeches at their wedding, so we had a huge fight*.
Now we never speak. There was a misguided attempt at reconnection a few years afterwards, but he was not the same person. It felt like she had taken his spark.
Anyway, as with any relationship I am no longer interested in, he doesn't feature in my frame of reference at all. I cut him off completely. She is happy about this arrangement (as I gather from mutual friends), but he misses our friendship.
--
* They did have speeches at their wedding. Her ex-fiance was his best man. And he called my mother a fat c**t.
_________________
If you break a crumb in half, you have two crumbs - George Carlin