difference between saachi and tara???

seriously now i dont understand whats the difference between saachi and tara... in yesterday's epi, when sachi went away from dining hall and shravan running behind her, it reminded me of shravan always trying to cajole tara... the way they hav shown saachi from the begining, they should hav shown her on shravan's side.. saachi was shown soo fluctuant, one minuite she says- i dont need any proof to trust my hubby, next minuite she ran away on seeing the pics.. (in a tara-ish manner) she should hav listened to what shravan was trying to tell her... so i dont see any diff betweensaachi and tara right now... yes thereis one... tara is atleast confident and she has self esteem..she wont get manipulated easily by others...in short.. tara can THINK...where as saachi CAN'T.....