In short it was basically a battle for C position in S2 with them being 1 & 2. People who felt DDD didn't deserve captain position coming with the BEJ wave and 1st robbed Guo of that spot even though Guo didn't want the captaincy.

Fans made things awkward for them so they distanced themselves with interactions and all to avoid more discourse but also their CP fans were fighting their houses too, it was just a huge mess they decided to stop it all. People then made a huge rumour theory involving YBY/DDD/Guo too because lol it had to be some fanfic moment or whatever eye roll.

But, they are good friends. Always been good friends since DDD was in X2 and they were training together. It's just unfortunate that fan rhythm got to them. But, also it gave Guo more power to be her own person and say fuck all this conventional river shit.

That's like a loose verison of it.