I dont see how Purab could ever justify why he dumped Jassi and ran off without a decent explaination! Ok he felt he could never replace Armaan in her affections - I feel this will be the excuse he uses! BUT he knew that all along! Why get her to agree to be his wife and then dump her as if he didnt know!
Armaan isnt perfect - he is far from it - but he would never ever have done that to Jassi and her family! Now fair enough you may argue that Armaan has done it to Malaika but he very cleverly got her to dump him and his parents are like her parents anyway. Plus he never loved her and has made this clear to her. Purab claimed nothing but undying love for Jassi and then he did the unthinkable to her.
Purab became like a son to Jassis parents and Bebe and then broke their hearts too! SICK SICK SICK.
I think it is unexcusable.