When my sister was just learning to walk as a toddler, my mom put the tree in the playpen that year. My sister could then walk freely in the house but not be able to reach the tree's ornaments. Not sure if this would work for cats as cats are climbers.
My sister (now grown) ties her tree to a hook in the ceiling to make sure it doesn't topple over as she now has two kittens. She has tried with her previous cats to prevent them from climbing her Christmas tree but nothing worked, no matter how many times she would water spray her cats in the tree. So she now secures her tree. Perhaps you can put up the Christmas tree, only on Christmas Day or find a way to secure it. There is no point in getting frustrated over your kitty during the holidays.
