Arnav is rude, mean and horrible to Khushi. Doing everything to make Khushi leave the office. Maan found out Geet was working and they had their shares of things, but he was never this rude or mean towards her.
Point 2 : Arnav-Khushi stories are different. Khushi is an orphan. Geet had a family. Arnav has a sad past. Maan's past never was shown. Geet was on honour killing, which didn't work and turned into an office romance. Arnav-Khushi are on a different angle.
Geet is about Geet , her struggles and Maan and her relationship. Geet was preggers to begin with. Their love story is SO different.
Arnav and Khushi on the other hand is termed to be a mature intense betrayl love story and I am so glad this show does not have much eye locks. I haven't seen one dovey eye lock yet so.. I mean they are different apart from 4lions, Nissar, Gul Khan, different tunes; mahi vs maula mere, and Arnav is super filthy rich.
Like they are same from outside, but once you go inside, they are poles apart. that;s just my take on it.