LOL this question is kind of feeling like puri Ramayan khatam ho gayi and puchho ki Ram kaun tha😆.
Imlie has felt a connection to Adi even before they were forced into marriage. Episode 9 is a very good window into the way their connection developed....they had an instant ease/instinctual quality in the way they talked.
The next major shift came when Adi saved her life in PD after the gunshot....whatever happened in those few epis really showed a level of intensity between them that was under the surface always but spilled out then. With Adi-Imlie, one has to see beyond the surface expectations of what constitutes attachment. They are attached cuz their souls connected.....it's not about behavior then....and there was a reason for Adi's behavior....he's not a bad person at his core. Imlie considers him her husband so any bit of kindness he shows to her gets amplified in her mind....that is why it's beyond a crush for her now. She's a simple girl and she defines relationships in these terms only.
Second all of that and wanna Add
There is no forumla to feel attached to anyone as such is there? one develops an attachment to even the most random things and people for different reasons given the emotional value of them.. idk how is this even a question that how could imlie develop an attachment bhai kehte hain insaan ko apne saaye se bhi attachment ho jaati hai.. yeh toh phir ek jeeta jagta insaan hai.. pyar attachment dosti, haq, ehsaas koi dekh ke nahi aate ke yeh Fit bhaitha hai criteria pe iske liye ok yeh nahi fit iske liye nahi.. People fall for the most problematic things and people knowing very well what they are getting into .. yeh toh phi rEK bohat Shareef aadmi hai by TV standards..
Imlie was already becoming Fond of him for his profession for his stand for her dadda for his sachaayi shaadi or no shaadi they had formed the bond even before that as nobody had ever taken that kind of stand or showed daring besides her dadda .. she saw a reflection of him in adi