My bottom line when it comes to herpes testing is to request an IgG and IgM test as the tests of choice.  You can conceivably have a negative IgM if you did not have a "recent exposure" but the IgG would be positive at any point during the herpes process.  There are rare false negatives on these tests - there may be far more false negatives when using some of the other tests available.   So the kind of test you take would be a key to knowing whether you had HSV2 and gave it to your fiancee - what typically happens is you don't go for testing till you have a rash outbreak - which explains why so many people are carriers, infecting others unknowingly - because without a rash, they typically don't get tested; once the rash happens they test positive - but they may have been harboring the virus for some time.   At this point, since you are both commited to each other - I know you are bothered by the fact that you may have given your fiancee the virus - it is also possible if she had relations before she met you that she was harboring the virus without an outbreak and gave it to you.  Remember stress and other factors sometimes contribute to finally having an outbreak.   I'd simply see a doctor as a couple to have the full ramifications of the virus explained.  I'd also make sure to be clear about herpes and getting pregnant/delivering a healthy baby (see my blog on this).