I realize that at this point I don't deserve the husband I have, but I can't lose him. It's true, I wasn't thinking of this at the time of the affair. I think for me (and clearly this is biased) that if my husband cheated on me once (one night stand type of thing) I'd rather not know.
Your actually wrong about the bolded part, it's your H who doesn't deserve you. He doesn't deserve to be cheated on lied to, exposed to STD's and have his health put at risk.
Your worried about loosing him but at this point that's not your choice. You unilaterally went out and made a decision to cheat on your H and put your M at risk. That was your decision to make, now it's your H's turn to choose, he gets to decide if he wants to continue to live with a woman who is not only willing to cheat on him but does not regret it. When you don't regret doing something it means you are not only capable but willing to repeat it. Can you imagine how your H would feel if he not only found out you cheated but you didn't regret "the connection"? How would you feel if it were the other way around?
I myself found out about my exH's ONS three years after the fact and I'll tell you it hurt more that he could look me in the eyes and lie to me for all those years. I felt used. He got to make all the decisions and took my choice away from me. I saw that I lost several years of healing and instead received additional years of pain and deception.
Others are right, overtime you will feel less guilt as you are able to compartmentalize things, and become a better at deception. You should also know that when that happens it is so much easier to have another A.
Somewhere there is a post about a 99 year old man who divorced his wife of 77 years for cheating over 60 years ago. The pain will not fade for your H over time, however, the length of deception will magnify it.
I wish you luck in finding the right path, it's not alway easy to do the right thing, especially after you did the wrong thing.