I have dated Jews, and not one of them has ever been offended by Christmas, hell they celebrated it with me, and got a Christmas tree in the house.
Seems you are a little snowflake, so toughen up and stop being a liberal snowflake looking to be outraged over this.
I absolutely guarantee you that your Jewish dates were NOT Orthodox Jews. There is no way I would be celebrating a holiday alien to me. Those were assimilated uneducated Jews---the same kind who are routinely panned here on FR for being liberals.