How do people with STDs meet new lovers?

[che]

I thought that it was something like needing to drink 3 litres of saliva from someone infected with HIV to contract it? That was a long time ago that I read that though.

That doesn't sound logically correct. Either STDs are transmitted through saliva, or they aren't. They wouldn't say saliva wouldn't give you an STD because you're only coming in contact with a small portion. Even 0.0001% would be a risk.

And on a lighter note, imagine looking at 3 litres of saliva and thinking about drinking it. Rofl.