This is a sensitive subject for me.
50-80% of the population has or has been exposed to HSV1 or HSV2 in their lifetime.
It presents as genital herpes or oral herpes (aka cold sores)
Most of those exposed to the viruses have the virus already in their bodies and don't know it - aka aysmptomatic carriers.
The herpes virus lives not only around the mouth, and on the genitals but also on other parts of the body.
Also related to herpes is the chickenpox virus and the shingles virus.
There are supression therapies available - my doctor has cited zero transmission between monogamous couples where one partner has HSV and the other doesn't over 3-4 years who use the supression therapies.
Herpes, while a frustrating virus - is more prevalent than people think - and only with a blood test can one be certain that they don't have the virus already.
Don't ostracize him. He probably already feels badly - and regardless of how personally squicked you are - communicating that with him will damage him and your relationship with him.