I can't say I've ever felt humiliated when another guy has fucked my wife. There may be some guys I wish she hadn't, but it's her choice to make.
With that said, I've never been present when wife had other cocks, and that may be a totally different dynamic, but it still has to depend on the guy.
I have a GF that was fucking another guy that I know from school days. We're not necessarily friends, but we aren't enemies.
He knows about us and I know about him, and the GF loves to share our info with each other. In other words, she told him when we had fucked, what we did, what it was like, and on and on. She would do the same for me and describe in detail when, how, where they would fuck.
So, it was only a matter of time before comparisons began. He made her tell him who fucked her better, who she liked fucking the most, and so on.
And she chose him in every category!
That has some degree of humiliation to think of him pounding her pussy as she's telling him she likes his cock and how he fucks her better.
But I know it's true and can accept that. I have health limitations that he doesn't, and he can do things to her I can't always do, if at all.
He also has other advantages I don't (like living MUCH closer to her; I'm 900 miles away, he's maybe 30), being (supposedly) divorced or otherwise single and much more available, so he can fuck her much more than I do.