I just found out that I have HIV. Have not told my Wife yet. How do I break it to her?

I guess you have to build up the courage to tell her as soon as possible. Face the reality and be honest to her. It's pointless to drag time and hiding it as eventually the truth will be reveal. She will need to go for a check up and under going tests hopefully your wife is not a carrier. Sorry to hear this. Go to seek professional help and counselling if needed as it's not easy to handle this alone.