IB, I am sorry you are feeling so sad. But it is ok. Really. You feel what you feel. There is no timeline, no clock. You get to where you need to be when you do.
Because you have had more upheaval - empty nest, moving, etc. it brings those feelings of loss closer to the surface again.
It is a huge thing living on your own, leaving your home, not having any children around. It takes time to adjust to it all.
You were always so hard on yourself. You have done amazing things during this time. And you have done them with dignity and courage.
So, time to go back to db101. Take care of yourself. Rest, eat, exercise, pray. Get your footing.
I know that you want resolution. I understand why you do. But there are some things in life that are just not resolved. And there are things in life that dont make any sense. Like losing a child or someone getting cancer. It's not the way life should go.
And so, it is best to let go of the need for resolution. There is no rational way to get it as this is inexplainable. It just is the way it is.
You are doing wonderfully. Just keep putting one foot in front of the other. One day, you will feel happy again. You will.