I am trying to find different yaoi's about abandonment. It can be about parental abandonment, family abandonment, or even good friends. I have read many yaoi's (angsty style ones) that kind of go into abandonment like
CUT
where the mother pretty much "abandons" her son, prefers rich men and left her son to do as he wished, so long he did not interfere.

Since you mention that you already read many yaoi with the same topic, could you provide us with your reading list?
Cold Light (Novel)
Ai no Kotoba o Uragaeshi