the odds are still very much in your favor, especially for HIV
. There are higher risks for other STD's, like herpes, chlamydia, etc. Test
as you were told at 3 months for a conclusive result. If you can locate your partner and go with her to have her tested along with yourself, that is a great idea and will be a load off your mind.
In the meantime....only have condom protected sex with your wife.
Try not to overly stress yourself....as you will just make matters worse.