Im stupid, can someone explain to me what happened?

These few chapters have been of the past, just before shulli died.
Basically jeremy I think that’s the older brothers name. It’s his wedding. The girl he’s getting married to basically told shulli that Jeremy didn’t want him to come to the wedding bc she was in love with Jeremy and jealous of the attention Jeremy gave to shulli. The church came up with the plot to kill shulli. Someone from the household reported that she was planning on leaving and they decided to assasinate her. Jeremy and the siblings await to surprise their mother but find out she’s died. The investigation starts.
This was a really rough explanation sorry hope it helped tho

Thank you very much!