S, You aren't hopeless, but you've got to find a way to deal w/your emotions w/o getting your h involved. He's a mess himself and if he can't help himself, he can't help you either. Come here to have your meltdowns.
Now, about the ow, what makes you think she's got the germ and has passed it on to your h? You do realize that you have no control over her, nor can you demand she be tested. The only person you have control over is yourself and you can be tested periodically, if you are scared that you have been exposed to it.
You'll find a way through the maze of emotions and get on the right track in time, but for now, definitely come here to vent.
The game isn't over, but if you continue to meltdown in front of him, you will surely shove him away further than he already is.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.