In a very challenging situation, you need to take extreme actions.
Desperate times call for desperate measures
To leave somewhere or start a journey.
Hit the road
To persist with something, to not give up.
Hang in there
When someone is (or feels) out of place in a situation.
(A) Fish out of water
To take a particular course of action, both literally and figuratively.
Go down that road
To become difficult to control.
Get out of hand
An important and obvious topic that everyone knows needs to be discussed, but that isn’t brought up or mentioned.
(The) Elephant in the room