Tbh i think it was a lot of things. First, his grandma died which left no support for estella in the castle, and with that reason, along with the fact that he knew estellas father had something to do with his mothers death made him uneasy about estellas intentions. Ofc he also thought that because he acted so cold towards estella, she wouldn’t want to be with him plus he’s seen the effort shes put into becoming the empress and thought it was all being pushed towards her

I dont remember but why did he divorce her in the first place?