Please note that I do not want any darkfic where Steve acts cruelly but doesn't care. It's very important that he feel regret. (This request may or may not be my method of coping with a certain recent development in the Earth-616 continuity.)
As for the other character(s), they can be all comforting and understanding or they can take the drill-sergeant attitude of "Snap out of it, soldier, we've got work to do!" (kind of like we've seen Clint do for Wanda when she freezes up), I don't care which. The point is that they correctly gauge what Steve needs to hear to get him back to his normal tree-beside-a-river self.
Any ships are fine, just let me know what they are.
(P.S. How is "steve(remorseful)" its own tag? Am I about to discover a whole new subgenre, or what's the deal?)