First off, stop blaming yourself for your H's infidelity. You may not realize it, but you are. You mentioned in your post all your faults (that he said), but I haven't heard anything about his.
First thing to realize is that the A was your H's own selfish choice. It has nothing to do with you. You didn't MAKE him unhappy. You didn't force him into the arms of another woman. You have resposibilities as a W and a mother that you were taking care of.
Has he been remorseful in taking care of your insecurities or has he blown them off? Have the two of you gone into C to determine what the cause of the A was in the first place? This is a MUST. DO NOT sweep this under the rug or you will find yourself here again. I've seen it too many times.
Right now you're experiencing the "2nd honeymoon" phase of recovering from an A. All will be great for a few weeks, but will revert to the way things were because the root cause hasn't been solved. It's like putting a bandaid over a festering wound. It's good for the short term, but eventually what's underneath is going to to continue being infected.
Also, start rebuilding your self-esteem. You DO NOT NEED your H to live. As long as you believe that, he will always have a hold on you and if he cheats on you again, you will be twice as devastated. Know that you can stand on your own two feet without him. He is the one that has alot to prove to you. NOT the other way around.
M-43 W-40 2D - 9 and 5
Emotion, yet peace. Ignorance, yet knowledge. Passion, yet serenity. Chaos, yet harmony. Death, yet a new life.