Sometimes people don’t want to discuss something when they know (based on previous experience) it will lead to a confrontation and argument, especially embarrassing if it’s a public confrontation.

On couple of occasion you wanted to discuss something with people who were intoxicated (not sure if you were too but you said they had a few drinks). That’s usually a bad timing and it’s a bad idea to discuss anything when under influence. So it’s smart for them not wanting to engage if they weren’t sober

It could be also that people don’t want to discuss something that was repeatedly discussed before. Rehashing something just doesn’t serve any purpose and it could be triggering.

It is also possible that people don’t want to discuss things with you because you previously ignored what they had to say or didn’t like responses and became aggressive. Next time people will avoid any and all conversations