12 saal baad Shahid ke career ko push Mila hai bebo thodi itna time rukti. In between she gave 1 300cr, 1 200cr , 3 100crs films so actually yeh Shahid ka loss h
That was by piggybacking on Khans and Ajay.
I don't think she has done a mistake, in fact their breakup has changed Shahid in a drastic way and he started to experiment in different types of roles and became much more versatile as an actor. Had they been together, then probably both their situation would be very much different.
Kareena looks happier with Saif and they seem to be very compatible and supportive towards each other. The decision of Shahid-Kareena's breakup was infact the best for both of them.