.....things that are important for my own personal health (like... did he sleep with someone and what precautions did he take?) Then again, would I really believe what he said (and then what do you do.. make them take an STD test even if they said they hadn't slept with anyone??)
If you actually get to that point, then yes, you do. I have had an STD test myself recently. (All clear, thank goodness.) And if H were ever pursuing me hard enough for me to consider R, then he'd be willing to take one himself. Protect yourself first.