Can someone tell me what this song is about ?

"move on" by witt lowry

So Witt in this song isn’t writing from two point of views. The point of view of himself and the point of view of his ex girl. Through the song we can tell he is writing it as though they are responding to each other through a letter. With key points like “Dear Mark” “This is our letter I sign this sincerely, Mark.” Now in the song Witt talks about how the roles have switched with the girl he was with. When they were together Witt would be with another girl thinking of her. Well no she’s with another guy thinking of him. She also goes on to say how she’s tired of Witt because he keeps using their story and relationship to put into raps. In the story Witt goes on to talk about how shes already with a new man who is with her who “loves getting head but doesn’t care what you think.” Therefore this song is about a letter he may have received from an ex of his but instead of responding with an actual letter he made a song out of it in two point of views and in the format of a letter. :) #TEAMWITT

Explanation:

i think it could possibly be b

a is the indefinite article