It’s possible that you may drift apart for a while, because these things happen despite our best intentions, but it’s also possible that distance will enable
Why question it when you can ask him directly? If he doesn’t have a response that makes sense to you, take the next step based on what your expectations are
That is entirely up to you, and should be based upon the circumstances, how you feel about the explanation, and whether you are ready to forgive if it’s worth