"Dear colleagues, with a heavy heart, I am ending my association with AAP," Damania said in a letter addressed to AAP colleagues, issued late last evening.
Damania, who unsuccessfully contested the recent Lok Sabha elections against BJP leader Nitin Gadkari from Nagpur, said, "My greatest regards for Arvind (Kejriwal), who is like an elder brother. All I want to request is that please do not have conspiracy theories over my exit."
The state party convener said she will never compromise on her values.
"I have never and will never in future compromise on my values. I request the media to respect my privacy," the 45-year-old leader said.
Damania, a crusader against corruption, refused to state any reasons on her sudden decision to quit the party, and said she only wished the "best" for AAP.
"Kindly excuse me, I do not wish to state anything except that I care a lot for my party and my best wishes are always with it," she said.
Reacting to the exit of the two AAP leaders, Mayank Gandhi told PTI that lack of communication at various levels and complaints against AAP committee members by party workers pushed Damania into tendering her resignation.
"Minor organisational issues like complaints against the behaviour of committee members by AAP workers and lack of communication at various levels were irritating Anjali (Damania) and Preeti (Menon). They could not focus on the major reasons for which they had joined politics. Hence, she decided to quit," Gandhi said.
"We have been able to convince her that a structure will be created for organisational issues and she should focus on what she is good at (taking up corruption-related issues). She (Damania) intends to meet all volunteers this evening to exhort them to refocus on our original goals of systemic change," Gandhi added.
Damania stood at the fourth position from Nagpur Lok Sabha seat during the recent election by securing 69,081 votes.
Gadkari won from the seat, with 5,87,767 votes to his credit, by defeating seven-term MP Vilas Muttemwar of Congress.