To be concerned by someone when faced with a stressful situation sounds like friendship, but are they one and the same?
Not exactly

There's a technical difference between companionship and friendship, according to Larry Shushansky, a rhode island based psychotherapist, "Companionship is the good feeling that comes from being with someone while friendship is more of a state of being with someone.
Friendship is more about the relationship that exists while companionship is more about the feelings that come from this state."