He’s still her Neal.
<3
I have a feeling that even *if* Emma chose to date Hook, Neal would never really move on from Emma or the dream of their Tallahassee. Sure, he could learn to accept a co-parenting arrangement over Henry and be cordial to Emma and Hook, but secretly, he would always carry a torch for the mother of his child. While he might learn to accept the status quo and would maintain a healthy boundary so as not to make Emma uncomfortable, Neal himself would find it downright impossible to find another woman who captures his heart as Emma does. Neal knows now what a huge mistake Tamara was, and she was his excuse for not going after Emma, which turned out to be the biggest regret of his life. I think Neal would end up spending his days alone rather than try to find a second-place substitute for Emma.
This is a factor into why I believe SF has to be endgame. I know, I know, there's always the argument that not every character has to end up with a partner, because a happy ending can be being alone and having your family. But let's be real here, it's a show about fairytales, so all of their main characters are gonna be partnered up as a means to their happy ending.
And the way they're writing Neal, he only loves Emma, despite what he had with Tamara, he never loved her the same way he loved Emma, and now he's focused on being a better man and that's inspired by his love for Emma. He is all about Emma, which is why I find it amusing whenever people want to ship him with any other character with actual expectation that it could become canon. Like, how many times does he need to spell out how he feels about Emma before people get the hint that he's not gonna have eyes for anyone else?
The fact that they've written him with Emma tunnel vision, and that they've written his long life as being a tragic story of one loss of love after the other, and that, like I said, the main characters will all end up with a partner...the only endgame that makes sense IMO from a storytelling perspective is that his happy ending is to eventually end up with Emma.