That might be related to why it's such a taboo subject - people fear that even mentioning the word 'suicide' will cause some people to starting making deliberat

That might be related to why it's such a taboo subject - people fear that even mentioning the word 'suicide' will cause some people to starting making deliberate plans to end their own life. (It's certainly a rather depressing topic, not suitable for small talk or dinner conversation, and people who are always bringing it up probably could use some therapist time.) The effect is similar to the statement, "don't think of a blue elephant" - it's pretty hard to not immediately think of some kind of a blue elephant (Dumbo the Disney character? A wild African elephant that got blue mud all over it? A painted elephant in a Indian potentate's parade? Etc.) Psychologists use the term 'ideation' to distinguish between merely thinking about a topic, versus obsessing over a topic, making plans related to a topic, and so on.