I don't know if I am right or wrong , but I think that Archana is NOT that much in love with Manav any more. She loves him and cares about him as a family member and as a dear friend , same like say Vandita .
She said that she could not bear to see him with another woman , at that time she did love him as her man . Now it is strictly a very caring platonic relationship . Manav too is responsible . he is the one hammering in her brains that they will always be part of each other's lives .Now Archana is doing exactly that .I a pretty sure that she has no man woman feelings for Manav whatso ever ..I don't think it will be very difficult for her on the day of divorce . She will go through it in an amicable manner . Sure, maybe cry little bit but not so much ...