one of the most frustrating and isolating things about being suicidal (other than being suicidal itself) is the way that once you've attempted, no one will ever trust you for the rest of time. any time you get too depressed (which is going to be often, because you don't get to be suicidal without being too depressed) everyone assumes you're a danger to yourself and that they have to step in.
and on the one hand, i can't necessarily blame them. i am, demonstrably, a danger to myself. i have tried to end my life on multiple occasions, two of which involved me getting briefly institutionalized. i have a track record, so it makes sense that that wariness, that pragmaticism, would be there.
but on the other hand, in turn i feel like i can't tell most people that i'm depressed anymore, because if i open up to them about how i'm feeling, they might think it requires intervention. i can say 'till the cows come home that i'm not thinking about killing myself, that at any given time i'm just regular depressed and not suicidally depressed. but there's always going to be that baseline level of distrust, that they'll think I'm holding out on them, trying to push them away so they can't stop me killing myself. and that causes me to actually hold out on them and push them away, so they don't institutionalize me without my consent.
people get this grandiose idea where they're some savior in my life, preventing me from doing something terrible to myself because they're the only one who can stop me.
and that's really frustrating and belittling when i'm not having ideation, but when i am... those times i wish that my suicide attempts had succeeded, that i could get into a fatal car crash, that something would end my life by a hand other than my own. those, i feel like i can't tell almost anyone about. the chances are just that much higher that they will get involved, because they'll think that means i'm planning something. they think my passive ideation is the same as preparing to attempt. and that's the real kicker, because being unable to talk about the passive ideation means that it just sits there and festers in me.
i do have some people i can talk to openly who know about my history and don't have that intent or distrust. but those people are few and i don't want to overwhelm them, and so it gets bottled up.
all that is to say. everyone needs to get more normal about suicidal ideation. and that can start with you. be a safe place in your suicidal friend's life. let them know they can say anything to you with no threat of institutionalization.