RL, uR is correct... you are loved for who you are. If they didn't love you, you would have known it many years ago. It's difficult to fake love for another human being when they are related by marriage. Do not say goodbye to them. You might be surprised when they find out about the separation. They may very well open their arms and pull you in for love and strength. They sound like lovely people.
I'm sorry to hear about your son. Yep, the empathy chip goes out the window when they are in mlc. It's a crying shame he didn't go to the hospital and be there for his son.
I'm sure your house will be rocking this evening and the tree will look fabulous. Take as many photos as you can. Christmas only comes once a year the pictures will be priceless as the children grow up.
Please don't all his behavior to ruin your holidays. Enjoy each and every minute because you can't do a "re do".
Have fun this evening!
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.