shared a foxhole

Experienced a difficult time or unique timebwith another person, usually your friend or, when at work, your partner(s).

It usually brings the people involved a bit closer to each other as they had a shared experience together.

We shared a foxhole together the night the car broke down and we had to walk 5 miles through the forest to get the the nearest gas station.

The patient was bleeding, vomiting, and pretty much dying in front of us. After working our asses off, getting covered in her blood and vomit, we saved her life. We shared a foxhole that night.