“I was left with a feeling of overwhelming sadness,”
That is the point. The purpose of Tisha’ Bav IS to feel sad. yo uhave succeeded
“but also the question how to channel that feeling.”
It dopesnt need to be channeled the point is being sad.
Sure if you want yo ucan use that sadness to ensure it doesnt happen again by working on Say, sinas chinam which chazal tell us is wha tled us to thsi mess in the first place.
but this is secondary. Tishaa Bav isnt a day of teshuva. We dont say Selichos, we dont lain vayechol we dont lain dirshu (not in the morning at least), we dont say avinu malkeinu. As chazal say Hashem closed the gates of tefilah.
The point is to be sad and mourn over that which was lost.
AY
“The original Christians were Jews. So, should we “join them” in their celebrations for the sake of some type of “unity” of mankind”
whats with this strange comparison to christians/christmas. do you really not understand the difference between Yom hashoa and christmas? IS that how far removed this strange shita makes people?
Out of curiosity , to you make thsi same false equivalence between joining/following when it comes to joining them in accepting government funds, or is that a special exception?