You are not alone. There are other people going through surprisingly similar circumstances and feeling similar emotions and that is why we are here. Please attend the meetings. They are invaluable.
Please don't do anything silly and please know that this is not your fault as all you have done is love so done who will NEVER reciprocate, as he is unable In His own sickness.
Maybe make a New Years resolution to never have to feel thus way again and to always remember that you are worth so very much more.
Bless you.