I read about a woman who almost died from an allergic reaction to water and I masturbated to it for 2 hours straight
What made you masturbate to a woman almost dying?
The thought of her dying made me horny.
Masturbation should be enjoyed so any harmless fantasy will make it more exciting and satisfying. As long as you separate fantasy from reality, your thoughts and pleasure are yours to keep for yourself.
That's pretty much why this keeps happening.
If it makes you feel uncomfortable, you can always talk to a sex therapist about how to quell this particular kink.