on the end when Nick knocks on the bath room door with Lily and Fred inside the bathroom.
I think
latex224 is on to something.
when Nick drank whiskey in Fred's secret room he opened up for some ideas how the confrontation with Lily can go so that Lily get's out of it on top:
1. She can hide Fred in the shower or even bathtub, then accuse Nick of having been drinking too much again that he is seeing things. Alternately, have Fred slip out while Nick gets distracted. Say Lily ask him to go and get her cloths or so... when she opens Fred's gone.
If she wants to confront Nick, she also have the other options (only works if she she triggered these scenes):
2. She can bring up the stripper BJ and accuse Nick turning the table
3. She can bring up Briana ("little Nick")