It's wired into our DNA to do this, and while we can be socialised out of it, you'll never get anywhere close to the near 100% you'd need.
Yet here we are, needing laws, cops, vaccines, and so on. Asking people to only have absolutely safe sex due to its external effects is about as useful as asking them to stop eating meat due to its external effects.
And AIDS is not considered a death sentence btw. It's not the 1980s
The HIV/AIDS epidemic would not have been nearly as serious as it was if people like you and the Catholic Church hadn’t advocated for it over all other measures.
It doesn’t work. Change your mind.
Getting tested is great practice, but you can’t rely on partners being diligent or consistent with that for your own safety.