yes but Mona was fighting cancer if I remember...so she was sick and she eventually died from the cancer
fact is so far gajra shown mouli is not in love with ishaan...where as ishaan --i dont know his background at all...so no comment on him...we dont know exactly what happened in mona life post break up...as gajra closely watched her life ..so we need to wait for gajra narrative at this point..just interesting point to watch out far is...weather gajra going to stick with reality or weather gajra going to give happy ending in serial to just please some viewers who are uneasy with hard reality of life...