Y'know I feel that Simi in her own way does love Abhi a lot. But her 'badi didi' values, her emotional dependence on the umblical cord prevent her from re-prioritising her life, so despite her love and her innate goodness she may not make a good wife.
Abhi values friendship and loyalty beyond anything (remember his dilwala line?), whether in marriage or other relationships (such as with RS, Mili and now Omi). So it likely he will stand by her as a friend no matter what the state of their marriage.