This isn't the only reason people want to kill themselves. My dad had cancer, and basically got locked into a ruined and barely usable body (in that he wasn't fully bed ridden but couldn't take care of himself or speak).
If he lived in a place with compassion he could have ended it cleanly. He didn't. Where he lived killing himself would be illegal, and would have been much harder dealing with the legality than otherwise. He had life insurance that swapped when he ended his job, he had to die naturally so it would pay out for us because there's no law protecting it.
So instead he suffered for around a year. He was kind, he didn't tell us (the family) what was going on, but about a month after he had the surgery which really f*cked him up to get rid of a tumor, the tumor was back. He just told the doctors no when they tried to help further, and died after 8 months of suffering. One might consider it suicide by inaction, but for some reason that's condoned and seen as strong.
My mom didn't understand this until a few years back when her memory started going and she was losing herself, and talked about how unpleasant life was and there being some alternative. when I mentioned that dad had wanted to as well (he didn't tell her, she couldn't handle it at the time). She expressed regret she didn't live somewhere else. Then she forgot about the discussion the next day. She spends her days with about 3 minutes of memory at a time and will till she passes.
End of life isn't just about suicide. They both wanted to live, but not in the irreversible physical form they were in. Neither legally had the option. Neither actually did it though. I bet my dad would have and I don't blame him if it was socially acceptable and legal.