I just reached out to the four people on Facebook who I do not have alternate contact info for. I told them I will be closing my account in a few days and gave them my contact information.
Within five minutes they all replied with their contact information. I'll be informing my D&D group tomorrow during our game. Friday, I'll deactivate.
It really is that easy. If you want to delete yours, do not let the fear of losing people stop you.