Weirdly, it's much easier to recover the second time around.
I think I've found it easier because now I see it more as a problem in my husband (like drugs or alcohol would be), then something wrong with me or the marriage. I think realizing that it's a problem he has, or a weakness of his, has made it much easier for me to accept and deal with.
I know not all affairs fall in that category, but regardless of the reasons for an affair, the response, or choise of participating in one is definitely a personal weakness or flaw that eventually needs to be recognized and dealt with.
There is no arriving, ever. It is all a continual becoming.