well durga started off being a matured lady who used to be the next big thing after dadi -aj ..
since she was first bahu of jindal bhavan so maybe it was her responsibility to run the house smoothly without doing mistakes ..
from the beginning she might have been trained like that ..
maybe buwa was there when she was new to the family .
we all saw how buwa treats bahu's ..
maybe buwa was dominating and ruling on her and aj too was pin perfect and never liked indiscipline ..
maybe she was adopted to there rules like be perfect ,do perfect ,make sure everything perfect ..
when saru-lakshmi came she handled them as buwa handled her maybe .
maybe she felt like a frog in a well which it thinks the world is that much as it saw ..
but when guddan entered things changed drastically ..
aj let go few rules which was followed in the house ..
aj -dadi forgave guddan for few errors which really might have not gone well with durga ..
she might be thinking why special treatment for guddan those rules which were laid on them why can't those apply on guddan ..
jealousy ,insecurity and ego hit her badly ..
slowly she realized her importance her respect is draining out and guddan is getting more attention which she always craved for ..
she feared if aj really accepts guddan as wife she will lose grip on the ppl and responsibility ..
so she always tried to rip there relationship ..
her main motive was to be next aj of the house so that lakshmi-saru is in her mutti..
insecurity in ppl will drive them to the lowest pit ..
eg--its the same as sister-in-law and babhi relationship rarely we see them jelling ...
jealous on bhabhi is common because they think there importance is fading off ..
---cycle of life u see ..