Hi Move...yes Happy Holidays. I am sorry that your dad has not been part of your life because it obviously was and is important to you. But since he not does not want to be, or maybe is just not capable to that type of relationship it may be best for your kids not to hear about him only to be disappointed like you have been. Maybe make the focus about your immediate family which sounds happy and loving.
We can not make someone change. We can not expect someone to be what we would like them to be even though it seems like they should want what we want! Like the family holiday thing. The situation with our dad seems to be his problem and not yours so it is not in your control. Sad yes, but hopefully you can focus on the others around you