The scientific reality is that most people with Herpes are asymptomatic, the virus causes no real health problems for a vast majority of people, and a vast majority (around 90%) of the Earth's population carries HSV-1, 2, or both.
He could have had the Herpes virus for many years, just not known. People get infected and remain asymptomatic, not having symptoms. You would need to research methods of trying to avoid transmission, if there are active outbreaks involved, and how to protect yourself.
Many people have the virus, and once you have it it never clears. Just some people don't ever show signs.
I have been with someone, almost the same age difference as you and everything, for over 13 years, who has the HCV virus, and all my tests continue to be negative at this point. Blood to blood contact for transmission is rare, but you would want to educate yourself to remove many of the fears you initially have then make an informed decision.
Monogamous relationships carry far less chance of transmission, but no one can say for sure it is a guarantee against transmission. It is just so rare it happening from normal sexual contact. Do some reading on it and you will see that the fears and stigma surrounding both Herpes and HCV are often misplaced. He would be very appreciative of your support and understanding, and you can find out about it together and see how you can support each other during this emotional time and how it will impact his health over time and what can be done to stay as healthy as possible. He will learn more about the health of his liver as time goes by and they do more testing to see how the virus has impacted his health. He will need someone to be beside him, even as a very good friend.
You seem very reasonable and I encourage you to do as you say and research these two things. I have a very normal relationship with my husband who is also sick from the virus, but it has not impacted our love life. It has made us closer as we learn how to fight it together.
Take care, C
HCV is usually not sexually transmitted, unless there is blood (CDC says monogamous relations are ok).
Herpes though is transmissible. Wearing a condom cuts your chances in half, but does not prevent it. Herpes comes through shed skin cells, from the whole genital and oral areas. Up to you to decide whether herpes is serious enough to discontinue your relationship.