I went to a lawyer and she petitioned the court for temporary use of the family home. She was sure that it would be granted. This would have enabled me to force him out. The police would have escorted him had he refused to go. Long story but I never did it. I ended up agreeing to let him stay (this was before we were divorced) until he found an apartment and it was awful. He did finally go. He said all those things to the kids too
If you aren't married then tell him to take a hike or you'll call the police.
I just dug in my heals and said he had to go and listened to (and ignored) his tantrums, blaming, manipulations, and comforted the kids as best I could by reminding them that a) adults have adult problems and I know it is confusing for them but mom and dad can not live in the same house anymore. It is not their fault. There is nothing they can do about it. I assure them that I will make sure they are OK. That dad has alcoholism and sometimes makes poor choices but he can take care of himself. He's a grown up, he's smart, and he *can* figure it out.
The scenario you shared above is exactly what would happen if I'd have let him come to my house this Christmas. He asked multiple times. He asked the kids to ask me - multiple times. Each time the answer was no. It was/is soooo hard. I had crying kids asking me. He actually left from his sisters (he's also homeless right now) and was just going to show up on my doorstep. She called me and I called him and said NO. He can come visit during the day but he can't stay over night, not even one night, or he'll never leave.
Honestly I got mad. Really mad and fed up and that helped me follow through. I'm all about keeping my home my safe area now and so I won't cross the line even one night - even if he was in recovery (which he is not). It is hard on the kids and I don't think they understand but it would be even harder to have him here and then force him out again.