Imlie's strength has already been established when she used presence of mind to save Aryan from 2nd bullet (i know rubber band vs gun was stupid af, but takeaway was presence of mind in critical situation)
And also when she made heaven meet earth to find a donor for him and bring him to hospital against all odds.
Being strong doesn't have to mean that we cannot have insecurities or triggers. She was triggered by someone who's her safe place. Imagine being attacked in your own home?
Imlie is also someone who's been traumatized not just in past year but throughout her 20 years of existence because of her illegitimate status. And that kind of trauma needs long TLC to heal, Aryan giving her courage, confidence and love for say a few months ain't going to cure it. She still doesn't know what it means to be secure.
Imlie's journey along with education and career encompasses her family as well, one is not superior to another. Being all independent working women, we know what it's like to balance work and relationships. So leaving family for career ain't and option equally as leaving career for family isn't.
Aryan is her husband and partner, they are eachother's strength. But if one of them is hurt it's the biggest weakness for other.