Between the ages of 10 (when my mother died - well actually mummy died when I was 10y5m8d old but if you say something like that people look at you sideways...) and around 20 I was desperate to die, with patches of being actively suicidal. I was held back mostly feeling it would be selfish for me to kill myself. There were people foolish enough to think I was a good/nice person & to love/like/care about me - however wrong they were to do that, I would hurt them by killing myself. I had my sister (3 years my junior) to look after & the house to help run & couldn't simply abdicate that responsibility. Discovery of my corpse (or witnessing my death) even by/for a total stranger, would be deeply traumatic & distressing for them: it would be cruel to do that to another person. Were any medical staff to be involved in things, the deaths of children & adolescents are particularly difficult to deal with - and again, they wouldn't know that I deserved to die - it would be wrong to upset people like that. Our GP was a family friend & I knew he would blame himself for not realising & getting me help: how could I place such a burden on a kind & gentle man who didn't realise because I was a bad person & lying all the time about how I was? From 12 I had a volunteer role with children - they were wrong to look up to me, wrong to like me, & INCREDIBLY wrong to want to be like me, but they did, and I would not only devastate them with my suicide, it would be setting a bad example.
I was also scared that Death Would Be Worse. That either there would be nothing; or mummy & granny would - as I did at that point - blame me for mummy's death & refuse to have anything to do with me as a result.
I knew everyone would be better off without me & I was desperate for the pain to end & to be with mummy again. I had the fears mentioned above, but also the awareness others would, mistakenly, believe that the world had been better with me in it & choosing to cause them pain to end my own would be a selfish thing to do.
I have been told since that what I think of as being happy is, in actual fact, severely depressed. When I feel depressed, I'm off-the-scale shouldn't-be-able-to-function depressed. I'm still going to count it as happy, because it feels so SO much a million miles immeasurably better. If I reached Real World Happy my head might explode. (So my depression goes untreated & I bimble on.)
In the most basic-literal sense, I do still think suicide [& I'm not talking about assisted suicide/Dignitas etc here] is selfish, but not intentionally so. Often people intend the opposite - they think continuing to live is selfish & they are setting their loved ones free. There is so much pain involved, so much stigma, so often no treatment or support is available because MH services are so overstretched.
Suicide leaves a trail of devastation in its wake, as so many PPs have noted. My father's best friend committed suicide when I was wee. I wiped all memories of him from my mind, unlike with people who died when I was a similar age - or younger - from natural causes. I have a weirdy-eidetic memory (though I don't remember my entire life, mercifully...) that starts v patchily from 9-18m & then kicks in properly. And he is nowhere to be seen, despite plentiful stories about him & a childhood fondness for looking at my parents' wedding album (he was best man). My father still questions whether he could have Done Something, Stopped Him; as does my aunt. Their friendship group drifted apart because it was too difficult to deal with the empty space & silences he should have been filling.
On average, a train driver can expect to kill someone every 10 years they are in the job. Which causes huge amounts of trauma & many (I'm afraid I've not been able to find exact stats) are unable to return to work even after counselling - oh & they no longer get any compensation to allow them some breathing space/to retrain.
This summer I had to call The coastguard out when a man jumped off Hungerford Bridge. I only caught the jump out of the corner of my eye, but I heard the splash. I then had to watch him in the water so I could tell the emergency services where he was. Thankfully, there is a lifeboat station close to the bridge & either on the way down or when he hit the water, he changed his mind AND he was a strong swimmer, so they were able to effect a rescue rather than a recovery. But I can't look into the water towards the railway bridge because it causes a flashback; I get anxious when I see anyone doing anything other than walking straight across the bridge or taking a quick photo; and I still have the occasional nightmare where they don't reach him in time. (Much to my disgust, a load of people FILMED him in the water. No attempt to call for help, their first thought was to get a video of a man drowning. They were happy to film a man dying in a truly horrible way - and he was so scared, too, it was really awful - I can understand if you caught a tiny bit because you were taking a video of you & your mates & he was in the background, but people were whipping out their phones & crouching down to get the best shot... I really REALLY do NOT like humans sometimes.)
Last summer I was on the verge of calling 999 for someone on Westminster Bridge. I could see them from my hospital bed & their behaviour made me concerned they were thinking of jumping. Just as I was about to call somebody walking over the bridge obviously decided the same thing as me & came back to talk to them & I think brought them along to A&E in the end (they came over the bridge towards Tommy's, the passer-by sort of steering them very gently). It was an absolutely awful feeling to be watching someone, terrified they might jump, but too far away to help them. I even had a mad moment of considering disconnecting my various lines & trying to struggle down there to get to them - I didn't mostly because if they weren't there when I reached the Bridge I'd have to guess if they'd walked away or if they HAD jumped... (I do not make the best choices when it comes to self-care, what can I say...)
Selfish maybe isn't quite the right word, but I don't think there is a word that expresses-explains it properly, and selfish is about as close as it gets in terms of "suicide has a devastating & lasting impact on people left behind/drawn into its orbit".