Having a life-threatening disease isn't fun at all. I've seen people die from life-threatening diseases and it's really, really unpleasant. As euthanasia isn't permitted in most places, doctors will offer palliative care to prolong your life - which IMO potentially increases the torture of your existence. Imagine not being to do simple personal hygiene stuff by yourself, or feed yourself. It's very undignified.
Depression does suck. I can relate to that - been there, done that. I went through a phase where I questioned why I was even bothering to be alive, because my MI [schizoaffective] has basically been steamrolling me every six months or so. However, I've come to realise that there is hope. If you have medication, take the meds on a regular basis. If one med doesn't work, try another one - or try a combination. There's a lot of meds out there and a lot of combinations. Do therapy. Practice some self-care techniques.
This might sound trite but things can get better. It can be a really hard struggle sometimes, but there is a light at the end of the tunnel.
Suicide by cop, btw, is pretty selfish - you can damage other people [esp. the cop who has to pull the trigger] if you attempt that method. Same with other methods involving other people, like jumping in front of trains. Jumping in front of trains is very, very messy. Plus you don't always die straight away.
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Said the apple to the orange,
"Oh, I wanted you to come
Close to me and
Kiss me to the core."
Think you're ASD? Get thee to a professional!