Friendship, of itself a holy tie, is made more sacred by adversity.

Trouble sorts relationships quickly. Ordinary friendship runs on enjoyment and shared time, and hard conditions replace that with cost, awkwardness and the requirement to be there when nothing about it is pleasant. What survives has a different weight, because both people have seen what the other does when it is inconvenient.

This works in the direction of giving as well as receiving. Somebody you know is currently in the middle of something and is not asking. Go anyway, without a solution, and stay a while. Being present badly is worth more than being absent tactfully.