What is the difference between Abstain and Refrain?

What is the difference between Abstain and Refrain? : 
Abstain : 

( 1 ) To keep oneself from doing or enjoying something especially taking alcoholic drinks

He abstains from drinks and drugs. 

( 2 ) To Decline to use one’s vote

At the last election, I abstained from voting. 

Refrain : 

( 1 ) To keep oneself from doing something

You should refrain from smoking. 

I hope she will refrain from hostile action.