To feel very uncomfortable about this conversation - WWYD?

[Dontwanttopanic]

I went out for lunch today with two work colleagues. The conversation made me pretty uncomfortable and I'm not really sure what I should do about it, if anything. Perhaps more accurately, I am worried that the conversation might have made work colleague A uncomfortable and this is obviously rather upsetting.

A is black. While the conversation wasn't racist, B talked at really quite some length about other people's racism (with many, pretty depressing, examples given) and how unacceptable it was. This lasted the best part of an hour. I felt that I was being drawn into it more than I wanted to be and my attempts to turn the conversation to other topics didn't seem very effective. This just seemed like an odd level of detail to go into in the first place and the length of it made me feel very uncomfortable. I can't quite put my finger on why but possibly it was because it seems unlikely that the conversation would have taken place had A not been of an ethnic minority. Possibly that means that I am also being accidentally racist in the sense that I am applying a different level of sensitivity to the situation because of A's ethnic background? I don't know. I am just quite upset at the possibility that A is upset because she is just lovely.

I felt quite embarrassed. Should I say anything about it to A, explain that I felt uncomfortable and hope that she didn't feel the same, but apologise if she did? (Or possibly that would make the whole situation worse?) I'm really sleep deprived right now so please bear with me if this is rambling and possibly not very logical.

I'd just leave it, probably. Or say something very casual like "Well, that was a very heavy conversation topic for lunch, I thought?" and see if she agrees.

Sound like you witnessed some bullying and racism by stealth

Is in doubt do nothing but avoid this lunch partner and when and if the moment arises check In with colleague

Remember it's work - so tread carefully as might not even be an issue for her

Sounds like colleague B was overinvested in trying to make themselves sound non-racist.

Kind of "oh look at what these other people have said/done - I'm not like that, give me a medal"

Must have been excrutiating for colleague A though.

I know, Fight. I'm certain it must have been. and I'm ashamed that I didn't do a more effective job of steering the conversation away. I was just a bit stunned.

I had "diversity training" at work once and I had a similar feeling. It appeared to consist of encouraging people to competitively list the most gross examples of racism they could think of while repeating that it was wrong but didn't give any proper examples of what the consequences of being racist were. But there was almost a sort of revelling in it, and rather than increase my knowledge (I know a lot about the law relating to racial discrimination) it came across as really amateurish and a bit voyeuristic and unnecessary.