Avoiding unpleasant or difficult situations is a significant risk factor in infidelity. To use Mumsnet parlance, it is a 'red flag' personality trait, but is unfortunately not one that gains much publicity in anything you might read in the media or in some of the worst self-help books about this issue.
The most helpful approach in infidelity is as another poster said, to realise that it never happens in a vacuum and that there will always be personality traits, attitudes and behaviours that have led up to that point and which eventually permitted those actions. Only if an individual works to identify them, acknowledge them and change them, can there be any long term hope for change. I'd therefore suggest your husband works on this area of his personality and behaviour if he wants to prevent repeat infidelity. Individual counselling could really help with this, augmented by reading and discussion with you and any friends he might have confided in.
Often an individual will measure his growth in this area by testing himself in a situation that previously he would have ignored or failed to tackle. Examples are being the lone voice of dissent in a situation where it would have been easier to have turned a blind eye, risking unpopularity by stating a contrary view, confronting a situation instead of running away from it. As anyone knows, an individual's comfort zone widens with practice until some behaviours become second-nature.
I would be circumspect if I were you about other people's projections about your decision to reconcile and stay in your marriage OP. The strengths you've attributed to your relationship are extremely positive and are noticeably about its ability to enhance your life. They do not relate to peripheral factors such as parenthood, finances or coupledom. You speak of individual qualities such as love, shared history and humour.
Something you might want to think about is that it is understandable if your own needs change as time passes. The early discovery period is often about the affair itself, whereas the next stage is to find links from past behaviour to what happened and to work on eradicating those behaviours in the future. As you've identified that you are repeating old relationship habits by taking responsibility again, this might be a good time to step back and pass that responsibility over.
That can be a make-or-break step in the relationship because it might feel counter-intuitive for you to stand back and for your husband to assume responsibility, but if you are to create new relationship patterns and scripts, this is an essential stage.
Your husband is probably waiting for you to make it a condition that he goes to individual counselling, whereas it would be better if he reached the conclusion himself that in order to change his lifelong behaviours and attitudes, only he can decide what needs to be done.
It is always a measure of progress when someone in your husband's position realises that he needs to change for his own sake in his quest to be the person he wants to be, regardless of the benefits that can be accrued if he becomes the sort of person others need him to be.