firstly she has found out a lot of things abt naveen but still it has not taken her anywhere in proving naveen's innocence. the more she tries to find out the more complicated it gets.
she is not totally convinced abt ritu. and is also unhappy with the fact that ritu supports raj but did not support naveen.
naina does have a soft corner for raj and trusts him.
but she is unhappy with the way raj is treating her. first he is rude to her and now he wants to win back her trust. but naina knows she cannot rely on raj from now on especially with ritu around and because she is officially raj's gf. if naina and raj get back together tongues will start wagging again. she respects raj and does not want to damage his career nor does she want to sway from her mission. if she depends on raj she will be coming betn him and ritu. she does not want to spoil the relationship with raj any further. i guess that's the reason for her odd behaviour.