it never rains but it pours, when it rains, it pours

(idiomatic) it is all Greek to me

all that glitters is not gold.

(idiomatic) all's well that ends well

when in Rome, do as the Romans do

it never rains but it pours, when it rains, it pours

a problem has come up

(simile) to be one's true self

Important people are given special treatment, which is unfair.

he who doesn't have a companion (brother) in battle; is unprotected