Re: Not taking bottle...
At 5 months I'd be surprised if she wasn't teething. The teeth may not break through for several months yet- my kids didn't get their first teeth until around 8 months, some kids don't get them until closer to a year- but even if the teeth aren't at the surface yet they're surely moving around in baby's gums and causing discomfort. So that could explain the night-waking, though increased hunger, a growth spurt, a need to reconnect with mama, or developmental milestones could also explain renewed night-waking.
Have you taste-tested the expressed milk? Some moms have issues with lipase, which can make stored milk taste pretty yucky.
Coolest thing my big girl said recently: "How can you tell the world is moving when you are standing on it?"
Coolest thing my little girl sang recently: "I love dat one-two pupples!"