I'm 20 years older than you, so I'll be brief with some facts, but I'm not trying to inform any decision you make. Just things I could say from starting in a similar place and then aging for 20 more years.
Your diagnoses at your age are a huge advantage. I was diagnosed only five years ago so being able to get into treatment is a big deal.
BPD is a cool diagnosis. I have it too. It was my first one! Then other dominoes fell into place. Anyway I'm just saying, it's not a picnic but consider that you get a little bit of superpowers relative to other human beings due to being sensitive. So even if life is short, there's that.
Suicidal ideation at this age is problematic in itself. After 20 years of being vaguely suicidal for reasons I couldn't determine, I have nothing to show for my life. I'm sitting in a tiny slide-out room of my brother's trailer and it's not slid out so I have like 1 square meter of space and no electricity and I can only get internet if I wake up super early so he doesn't need the internet cable.
Yeah, it's an ethernet cable in 2024.
My own feelings about somebody suffering at your age the way I did are not related to you or your choice but they do exist so I'll make a note that it makes me feel sad for you.
My biggest worry for you is that you will not make your mind up either direction and someday you will find yourself huddled in a tiny corner of your weird brother's trailer pushing age 40 and wondering all the thoughts that plague a person like me. Don't be me... live or die. Listen to Yoda. Do or do not.