Having chicken pox will in no way protect you against getting HSV 1, no.
Unfortunately, we don’t have transmission rates for people who have HSV 1 – either to someone else’s mouth or to someone else’s genitals. This is a very frequently asked question, though, not only you want to know the answer.
I will tell you that the pictures of HSV 1 usually shown on the internet are NOT typical presentations but terrible ones. Some people, with first infection, both genitally and orally will get multiple lesions, true. However, if a person knows that they are at risk for acquiring a new infection and act very quickly to obtain antiviral medication (or better yet, have it at the ready to use, just in case, then the outbreak can be limited substantially. Most people with oral HSV 1 have between 3-5 cold sores per year (genitally less than one per year). And YES, daily therapy by her, in this case, can reduce the frequency of cold sores appearing and likely also reduces the frequency of viral shedding. I, for example, have had cold sores since I was a child, and really don’t like them at all. So I take daily antiviral therapy and have reduced the frequency of getting them by probably 90%. When I feel one coming on anyway, I just up my medicine some and can stop them in their tracks, not going on to a full blown cold sore. Though research suggests that the medicine is not as effective for HSV 1 as it is for HSV 2, the difference is not all that significant at all.
I think if you are involved with a person who has HSV 1 orally and want to take a small measure of risk of getting HSV 1, it would be helpful if she was on daily therapy (acyclovir 400 mg twice a day) and somehow, either from her or from your own health care provider, have some antiviral therapy on hand in case you do contract herpes so you could start using it right away. Most people do not see side effects from taking this medicine. Avoiding contact during outbreaks and at the very start of one is certainly helpful, yes. The reality is that people can also shed virus between outbreaks.
Terri