Hello. First, I am not Protestant; I am Wiccan. Secondly, I sincerely believe that JC and Mary Magdalene had a very genuine relationship; and I don't see how anyone can see that they did not. But, where does "adultery" fit in that relationship? To my knowledge, neither one was married; or do you know something that I don't. JC did not commit adultery with MM and vice-versa. I do believe, like I stated above, that they did have a man-and-woman healthy, vibrant relationship--and why not?! They were traveling together all the time (so that invited a closeness!); she was the only woman in their group; she was young; JC was young; both were healthy; there were plenty of caves just waiting to be christianed, and I'm sure that the rest of the disciples, especially Peter, were just wishing that they were in JC's sandals! But commit adultery--not even remotely! If my understanding of "committing adultery" is correct, it means infidelity, disloyality, falseness, betrayal, even treachery. Did that relationship appear to be any of those adjectives/ verbs/nouns? I think not. Both were certainly a willing partner in a/some willing action(s). And most important of all, and especially in this case, neither one was married. "Commit adultery?" Not even remotely!
And you also speak of "the woman at the well. . .with a woman taken in adultery whom He dismissed so lightly." Now, these two incidents I cannot comment because I do not know what you are referrring. But, I am sure that whomever he "knew" while on the road, that he did not have to get to "know" married women or whatever kind of woman; we are talking about JC here. I'm sure he was able to get to "know" whatever kind of woman that sparked an interest, however remote that interest might have been.
But commiting adultery, again, not even remotely!!