<human>: Could you distill the essence of the text into 1-3 sentences?

My girlfriend of almost a year and I are going up north to visit her family for Christmas for a week. We will have been living in an apartment together for nearly five months by the time we go up there.

We will be staying at her father's house for half that time, and he has expressed to her that he would like me to sleep on an air mattress while she sleeps in her bed. He is a Jehovah's witness, if that is of any relevance. 

Her and I do not agree with this rule and she wishes for him to treat her like an adult in his household. Also as mentioned, we already live together and share a bed every night, and we find the rule a little unorthodox. 

I am excited to come visit and meet her family, and have respect for her father and and his wishes while we are visiting, but I find this restriction to be unnecessary and limiting.

How can she/we help him understand our perspective without coming across as rude or disrespectful?
<bot>: Visiting girlfriend's hometown for Xmas, meeting her parents for the first time. Father doesn't want us to share the same bed, but we already live together and want to make him see things from our POV.