With suicide, there's only loss to be had, and nothing to gain. You might think "it will stop the pain", but pain isn't a complete negative in itself. Painful memories can actually make it feel better when good things happen to you, because of the contrast. If someone's never known any pain, they won't enjoy something as much as someone who's been through it all.
With death, you're also giving up on all chances of happiness, you're giving up on everyone who loves or even likes you at all, and you'll potentially cease to exist entirely. There's no guarantee that there's an afterlife, it might just be a whole lot of nothing, and that would suck. You've only got one shot at life, so live it out and experience it! Try some new things, you might even find something that gives you great joy- a hobby or even a person, or something.
You can get through this! best of luck.