I don't really get it, since if you're dead you'd never know?
Unless you mean like trying and deliberately failing to see if people care? I get that, but I know that people really do care about and love me. My parents and family at least.
I cannot be bothered to attempt suicide for attention, because I know what reaction I'd get from my family - the same as I got the last time, 8 years ago. Anger and disbelief. Back then, I had two-three people pay attention to me after my attempt, the people who have since been long gone from my life. If I wanted to attempt now, I would not inform anybody of my intentions because honestly I'd just upset people who barely give a fuck about me anyway.
The paradox is you won't know if they love you if you're successful. But I get it wanting to commit suicide because you feel like no on loves you is valid. But you haven't met everyone in the entire world. If love is the problem, then go find love, because it won't always come to you.
To paraphrase L. F. Céline, people only like to talk about their own problems and try to unload their misery onto others, it is very hard to find love in a world like that, especially after you reach a certain age. Here is the quote anyway:
"Why kid ourselves, people have nothing to say to one another, they all talk about their own troubles and nothing else. Each man for himself, the earth for us all. They try to unload their unhappiness on someone else when making love, they do their damnedest, but it doesn't work, they keep it all, and then they start all over again, trying to find a place for it. "Your pretty, Mademoiselle," they say. And life takes hold of them again until the next time, and then they try the same little gimmick. "You're very pretty, Mademoiselle..."
And in between they boast that they've succeeded in getting rid of their unhappiness, but everyone knows it's not true and they've simply kept it all to themselves. Since at the little game you get uglier and more repulsive as you grow older, you can't hope to hide your unhappiness, your bankruptcy, any longer. In the end your features are marked with that hideous grimace that takes twenty, thirty years or more to climb form your belly to your face. That's all a man is good for, that and no more, a grimace that he takes a whole lifetime to compose. The grimace a man would need to express his true soul without losing any of it is so heavy and complicated that he doesn't always succeed in completing it."