Did I miss something (ep 7 spoiler)

Possibly a ruse. Maybe Shetty convinced Cate to make it look like Shetty killed herself.

Otherwise, no idea.

Shetty genuinely loved Cate as a surrogate daughter, and thought that love (because it was sincere) would keep Cate on her side

But Cate was beyond manipulation at that point, and had already adopted her “supes only” agenda. Basically, she’d become Magneto, a supes-supremicist willing to kill all normal humans.

Starting with Shetty