My Sweet Sister

One of my sisters is 15 and we are extremely close. After she graduates high school she wants us to get an apartment together. She’s going to get a morkie named Louie and I’m getting a Boston Terrier named Leo. When we get older she wants us to buy land together and build 2 houses, one for her family and one for mine. Underneath the ground a secret tunnel will connect our houses so that we can visit even if it’s storming. She’s buying the pool and I’m getting the in ground trampoline and swings for our kids. She wants 8 kids, she wants to adopt some of them from around the world. Sometimes she sits and tells me about our futures for hours. She has it all figured out. My sister loves me a lot. She tells me every night. Not many 18 year olds have a 15 year old sister that they get along with so well, I’m extremely lucky.
My sister doesn’t know how unsure of the future I am. She doesn’t know that I lost so much weight from starving, how much time I have spent throwing up everything I eat, how many scars I have on my thighs from nights I lost control, how bad my anxiety has gotten, and she especially doesn’t know about my suicidal thoughts. I don’t want to be alive anymore, I really don’t. Would it be fair to her? No. It wouldn’t be fair to any of my family or friends. This clearly isn’t a feeling that is just going to pass, I’ve had it for a few years now. I don’t want my future to be ruled by mental illness, but that’s how it’s looking like it’s going to go. I’m unsure of how to save myself… but I know my sister needs me.