Like has she broken down to you about having feelings or attraction for this guy or something?? Or does she vigorously deny there's anything to worry about? Speaking of which - has the issue even been confronted? Or is it more of an insecurities running wild type of thing?

Not trying to minimize anyone's feelings either, I promise. But I've had a number of "work bros" throughout my career (where there was zero zero ZERO attraction whatsoever nor any risk of it) and I figured maybe I could offer some insight from a "work sis" perspective lol..

The thing is, when I went down your list of criteria... I would say that a lot of those criteria fit my "work bro" dynamics as well (except for the lunch "date" thing... sometimes you just grab food with people man lol. And now that I think about it, it was almost never one-on-one and always in a small group).

With my last work bro, I actually made a point to become friends with his wifey also. So, outside of work, they're a package deal. And if I check my phone, I may have a ton of text exchanges with him but I also have a significant number with her as well as group chats with the two of them together. If I hang out with them, it's usually through her because she's the social secretary of the two. I've met a bunch of their friends and family and they've met a bunch of mine, etc. It's honestly just the most platonic vibe on the planet, and the thought of anything even remotely suggestive turns my stomach.

But if she was the insecure type (which I don't suspect she is but I don't involve myself in their relationship), I could see such a partner itemizing all of those things you mention and perhaps connecting dots that aren't necessarily connected.

In my most recent case, I think the work bro and I became tight because we were the only 2 black people in technical roles in our unit, which just helped in terms of having a support system/alliance when bs arose as it always tends to for black professionals. Plus, our offices were situated across the hall from one another so there was always opportunity for banter or venting or whatever. He was also one of the strongest with his skillset around, so I eagerly and proudly sought help/mentorship from him many times too. And in the reverse, he needed less from me on anything technical but I often had his back politically in meetings or to leadership or whatever.

So ya. Unless there's been some confession (from at least one party) of feelings or attraction, I don't know that I would read as much into the dynamic. Careers are stressful. I always leave every job with at least a couple super-close friends. For me, alliances are as much about coping as they are about networking. I don't know the age range here either, though, which might be a factor. What industry are we talking about?