As for what happened at today's year end party, I'll just let it go.
I'm already really forgetful, so I don't need a so-called "forget the year party."
In many Japanese companies, new workers are required to do a short performance at an end of the year party.
Time to get together and forget the year... what a terrible year, good thing a new one is coming. This get together is a year end party.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.