Needing suggestions on "The Talk"

I'm 29 and I've had GH for 7 years now and have had "The Talk" with only a few people since I really shy away from dating.  Anyhow, I just starting dating someone about a month ago and can't seem to bring myself to have the conversation so I'm debating on just ending the relationship instead.  I've tried a few times to talk about it (thought I'd just bring up cold sores first - thought it might get the convesation started) and before I got into any details about me having GH, he freaked out and said that he would rather have cancer than a cold sore.  I explained to him about how common the disease is and gave him a few facts without disclosing details of my infection.  He is a really great guy but sadly misinformed (and terrified) about the disease.  I would love to hear any advice that anyone has on this.  I really don't have anyone to talk to about this as I pretty much keep this part of my life a secret.