To hell and back

Been through hell and back. When someone survives, overcomes the worst of things in life and gains inner strength as result. Living through combat and going back home would definitely be to go to hell and back.

Endure an extremely unpleasant or difficult experience. (ref. Oxford Dictionary)

"В ад и обратно" Пережить большое количество событий (преимущественно негативных/тяжёлых) и вернуться в стабильное состояние.
Аналог "Пройти огонь, воду и медные трубы"