So I think that you are referring to the use of the IgM test in him and the IgG test in you.  In reality, these tests are not useful for timing the date of infection, though IgM tests might be helpful for that purpose with other viral infections, just not herpes.  Did he get a swab test done of a lesion?  What was the index value (number) associated with your IgG positive result?  Do you know if he had an IgG test done or just an IgM test done?  If he had a positive swab test of a lesion and a negative IgG test, this strongly suggests new infection - he had virus present on his skin but not enough time had passed for him to have made IgG antibody.  That would suggest that you infected him, yes. 
If you both have HSV 2 infection, there are no more worries about this between you - you can have sex as you wish without concerns. 
So about 80% of those infected with HSV 2 don't know it so you are not alone.  If you change partners, you will need to disclose this information to others and may wish to consider daily antiviral therapy to reduce the risk of infecting another person.  Please let me know what other questions you might have.

Terri

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