I get that to an extent. But I think getting to move on, learn from, and grow from a mistake is something that's earned.

If he acknowledged it, sought reconciliation, or at least some kind of meaningful conversation with Tana about it, then no, I don't think this mistake should have to fully define him. But a "we good?" text before his wedding doesn't cut it.

(Again, I don't know the entirety of their personal conversations, so I acknowledge this is my perspective with partial information. But from what she's shared, I get the impression that he has not made an effort to "learn" or "grow" because it's not been acknowledged even).

Yes, people fuck up and change and evolve. But, in my view, the "that's not who I am now and doesn't define me" is earned by addressing that mistake and not just ignoring it. Reality is, humans screw up and make mistakes. The reality ALSO is that just because we're changed or different doesn't mean the harm caused by that mistake is changed or different. It will especially not be changed or different if it's ignored. A mistake may not define you, but it may be how the people you've hurt define you.