It IS hard to trust again after such betrayal, but it can and does happen. One of the pivotal changes in my view on the whole issue was this:
I realized that I really could not control what my H did or will do. That he COULD betray me again. What I have the most trust in NOW is my ability to handle whatever may come. I don't project negatively into the future, quite the contrary. But having been through the grinder several times, I KNOW on a deep, spiritual level that I WILL BE OKAY no matter what. To me, that is the essence of trust. It's also a very powerful stance as it does not rely on what anyone else says or does.
Of course on a real life day to day level it sure helps when our S's reaffirm their committment to our M's, say how sorry they are for having hurt us, etc.
Be prepared for conflicting feelings (such as you already had today! ). They are par for the course.