When a depressed person reaches out, the situation is quite often serious.
It's likely to have been present for several weeks, and any recent event that we think just started the timeline, may in fact represent the last straw.
We should therefore refrain from anecdotes or suggestions or remedies, and refer that individual to professional help immediately.
If you encounter someone in this situation, the best thing you can do as a friend is to get the individual an appointment, and take them to it.