I has a horrible childhood and Xmas time was some of the worst time’s for me due to abusive parents. When I left home, before I had children, I’d gladly ignore Xmas, I’d either go on holiday or sleep through it. It only stirred up negative feelings.
However, when I chose to have children, knowing that Xmas is a things kids get excited by, that's how it is here, I knew I would have to make the effort to make our Xmas time special. If your kids now don’t want that, that’s because they’ve picked up on that from you. I think that’s unfair.
Those first few Xmas days, I put on a smile but by bed time I’d be in tears, past memories and the pressure for me to make the day special was overwhelming. I got therapy because that wasn’t how I wanted my life to be. I had this lovely partner and two beautiful children and I knew I didn’t want to make them as messed up as I was and have weird Christmas time’s because I hadn’t dealt with my past trauma. I can still find Xmas difficult (I think a lot of people do) but on the whole I enjoy it and for my kids, along with our summers away, it was/is their favourite time of year.
Your ex is a nasty waste of space from what you’ve said but you can’t change him. Even though he doesn’t have them a lot, I think it’s important that you do spend Xmas with your children every other year. Do some things together that you will enjoy, put a couple of traditions in there, I think it’s important for their future relationships and for if they have children in the future. If you spend quality time together, they’ll soon know that Dad might have been able to give them all the stuff, but mum was the one who really made an effort. And when they get old enough to explain your reasons for struggling with Xmas, they’ll really respect that you did that for them. I know my kids do now they’re older teens.
As for him possibly turning up to drop them to you and you just not being there, that could be extremely damaging for your children. He’ll no doubt be angry you’re not there, they’ll feel very unwanted. If he had them last year, I think you should be available this year. If plans really can’t be changed, talk to your ex, tell him he can’t change what he agreed on previously and hope he agrees. But from next year, you need to do every other Xmas, regardless of the days he’s had them in the year. You’ve said you’d rather he fell off the face of the earth, then take every opportunity with your children and maybe he’ll just be faded out. He doesn’t sound like a good influence over the kids with past violence and his answer to everything bring to throw money at it. It’s not fair on you or the children, in an ideal world parents stay together happily or are both reasonable and interested in their children so coparent well if they split, but that’s just not real life. The more he’s around the kids, the more damage he’ll do. And with Xmas being a big thing here, that time of year will likely do more damage than other times of the year as it be etched in their memories, like it is for you and me. You can change that for them going forward.