Light at the end of the tunnel
Definition 1 of 1
Pro Tip 1/3Positive Outcome
Use it when expecting a situation to improve after difficulty or darkness. 
Despite the struggles, he believed there was a light at the end of the tunnel.
Pro Tip 2/3Extended Metaphor
It's a metaphor comparing trouble to darkness and hope to light. 
Studying hard was tough, but graduation was the light at the end of the tunnel.
Pro Tip 3/3Emotional Relief
Can express a sense of relief after anxiety, stress or uncertainty. 
After weeks in the hospital, her recovery was the light at the end of the tunnel.