Oh and if you decide to test, ask for an IgG type specific blood test. Don't let them do an IgM test. It's unreliable and you shouldn't have to pay for that.
You don't need to tell him. Have you considered getting a blood test? Have you talked about STD testing? It's possible he could have hsv2 (or something else) and not know it. Most people don't have symptoms when they have an STD.
I think if you test positive, you can tell him about your ex, but as it stands now, I don't think he needs to know. It's not really a good idea to share your ex's status with someone else - that's his business, and it may be that there is no reason to share it.
Good for you, though, for thinking about prevention. :)