First, let me reassure you that your emotions are valid and "normal". You will have times you feel calm and in control and strong. And then you will just fall apart. My IC explained to me that it is very much like PTSD (post traumatic stress disorder) which many of us probably do actually suffer from to some extent. What we have been through is trauma. When people have been traumatized, they will react emotionally to "triggers" that may seem small or insignificant or illogical, but that doesn't matter. You need to give yourself a break about that and let yourself feel what you feel, and then try to move on.
Also - your questions about are you strong enough to do this and does he even deserve it? Absolutely normal too! I struggle with those same questions every single day, many times a day... even when we are having a good day! Because what has happened to us is absolutely the deepest betrayal possible. Of course we feel this way.
Yet... every time I struggle with that, I seem to find some strength somewhere to keep going. And, I look at our kids and think about how they deserve to have mom and dad fully involved in their lives, coming from an intact home. I think about things I've read about success stories and couples who have not only survived this but created a M that was better than ever before. So, I allow hope back in. But I am also realistic that we might not make it and I will be ok if we don't.
About your H's resistance with MC, try to let it go. The WAS often will waffle on things like that because, as much as they may be sincere in wanting to make things better, they know that C will make them face things that will be hard. So, they resist, then move forward, then resist again etc. It is the dance you might as well get used to now. You'll be doing that dance for quite a while. I find once I recognized that and don't freak out everytime the resistance comes again, he comes around to moving forward sooner.
You are still doing well, you are still strong, and things are still moving in a positive direction. A bad day every now and then doesn't change that!