Afraid I have waited too long

[adinva]

Avoiding confrontation does not create peace. It creates hidden conflict and resentment.

Using the tree, you don't put one up because you don't want to say anything to her (aka be confrontational) that might upset her (mind reading) so instead you're miserable, which she will see, and you have no holiday decorations, which will also be a noticeable change for her. You haven't avoided conflict, you've just shifted it around.

Alternative, you say I want a tree, I'm getting one let me know if you have a problem with that. She says OK. Or she says that will bother me can do xyz, which you can consider. So instead of finding out how she feels, which is loving, you anticipate the words in her mouth, and avoid them, which is fearful and leaves both of you potentially feeling worse than before.

Be careful polite is not a mask for something less noble, like fear.