bani's anger is justifeid with the lack of trust n honesty from jai, with regards to roshini n her bro - more so because she heard it from some1 else. jai may have announced his 'your my wife god dammit!' speech, but has yet to implement it into practice, of giving bani her true place as his wife, otherhalf n most importantly confidant!!! within whom he should b able 2 share anything n everything!!!
as for adi not knowing that rohit's father is roshini's bro - may be at that time be had his blinkers on for jiggy madam, n could not see beyond that - he might have been in the process of wooing jigasa. hence he don't know abt the park rd or street raaz - n so was kept out of the loop. also he might have only been introduced to roshini because she was jai's girlfriend at the time - but not introduced to the chopra khandan!
plus after the incident the raaz gang split n went their separate ways. so any links left between both families were never properly established, but instead severed indefinetly. that is until now......