Archana is totally loving her new found relationship with Deshmukh family. She feels like finally she belongs to this family, that she has been accepted by them, something she has been trying so hard for so long. Savita who was never kind to her as a MIL, even before all the troubles began, has now started loving her finally. And all of this positive development in her life has given her some kind of euphoria (elation😉) that all her perseverance and good deeds has paid off, making her react the way she did today.
Archana had looked happy when she marked a date in calendar for Shravani, informing her that it was her Baby Shower and she looked happy even today. If anybody looks excited about arrival of Sachin's child in Deshmukh's family then it is Archana, even more than Shravani herself. She wants to be part of welcoming the baby and promises Savita that she'll not give her a reason to complain. Only her family is not able to understand why she is doing so much for them when Manav and Archana are going to get divorced in few days. She reiterates that she want to live rest of her life with the happy memories that she spends in this house, happy memories that didn't start happening until recently for her.
Only I wish she hadn't said the things she said next that her relation with them will be the same even after divorce and that she will be with them in all their happiness and sorrow. What a poor script writing, looks like a job of novice script writer. If not then someone has to teach Archana the meaning of divorce. She is getting carried away with Manav's 'always be friends' ideology.