Chronology as i understood:
Rashami goes bankrupt due to family disputes..not literally..she is going through divorce.
She picks up dsdt in 2017 meets Sid and their relationship/fling starts.
They broke up in 2018 beginning and Sid leaves the show.
She meets Arhaan in 2018 and emotionally supports or brings her out of loneliness..
That's why she/her brother called out to Arhaan that u didn't make me.
They offered bigg boss in July 2019 and she enters it in Sep 2019..