oh well you definitely are right about her past contributing to her mental health, but it doesn’t necessarily explain the reason behind her attempting to murder her own son twice. i don’t know if you remember, but there was a scene where she began murmuring to herself as if talking to her husband in the past. it seems like he didn’t care much about her, cheated on her and got into fights with her often. i definitely think that contributed to her current state, or maybe it was the “last straw”
I'm too lazy to read all of the replies so someone might have mentioned this but I think the mom said she wasn't given much love as a kid and wanted her son to have it (when she was looking for him at the front porch of that girls house) I'm not sure if that was a bluff or what but maybe she wasnt lying about not getting enough love. It would explain why she was talking about the happy families when they were near the spot she dropped her son when he was 3
Like there isn't a complete backstory on her, yet. So why attempt murdering your son? Why not leave your husband, if you hate him and his family so much? What is she trying to break free from?