last beh tahan with ppl

ok...i will promise not to bad mouth ppl again on this site and save all the dissatisfaction to myself. but why??
just let me do it for one more time and then i will really not say another word about someone else.
this time it is my housemate...the new one. she takes forever in the bathroom and our water bill has rocketed since she came. i dunno what she did. that day i waited for 15 minutes for her to come out...she was taking her bath only...and this one she did not even wash her hair. i could hear water flowing and splashing the whole time she was in the bathroom. (i had to wait for her to come out to open the front door for me) imagine if she washes her hair, she is inside for a minimum 25 minutes.
and the wooden door of the bathroom is growing fungi! wait till i show the picture. how she splashes around in the bathroom god knows lah. the door is going to rot soon.
she is a cleanliness freak...that one i am sure. her room is spick and span but i won't say the same about the downstairs toilet cum bathroom which she is only using. i have never seen her wash it. how do i tell her to do so without offending her?
i try to ignore all her pecularities and live my own life in the same house...but there is bound to be a limit i can bear with. for now, i will wait till the door of the bathroom breaks down.