What the treatments are, and what the evidence says
Two things held together. Seeking treatment sits inside the tradition rather than outside it, and it is put in the imperative. Servants of Allah, use remedies. And separately, there are treatments for this specific period with real evidence behind them.
The review below found that cognitive behavioural therapy helps in the perinatal period, both for treating low mood and for preventing it, and its author is clear about the limits: the studies used different treatments, different comparison groups, and rarely followed anyone up for long.
The second study matters for a different reason. When women who screened positive for depression after birth were assessed properly, a meaningful proportion turned out to have a bipolar spectrum condition rather than depression alone. That is precisely why no course should be sorting this out for you, and why the answer to feeling like this is an assessment rather than a guess.
Qur’an and Sunnah
Usamah bin Sharik said:"Some Bedouins asked: 'O Messenger of Allah (s.a.w) shall we treat (our ill)?' He said: 'Yes, O worshipers of Allah! Use remedies. For indeed Allah did not make a disease but He made a cure for it' - or - 'a remedy. Except for one disease.' They said: 'O Messenger of Allah (s.a.w)! What is it?' He said: 'Old age
Jami' at-Tirmidhi 2038graded sound, albanifull report
Narrated Abu Huraira:The Prophet (ﷺ) said, "There is no disease that Allah has created, except that He also has created its treatment
Sahih al-Bukhari 5678graded sound, sahihaynfull report
What the research says
Sockol LE (2015). A systematic review of the efficacy of cognitive behavioral therapy for treating and preventing perinatal depression. Journal of Affective Disorders, 177, 7 to 21 doi
Cognitive behavioural therapy showed benefit for both treating and preventing depression in pregnancy and after birth. The author flags that the treatments studied varied widely, that control conditions were inconsistent, and that few studies followed women up over the long term.
Wisner KL, Sit DKY, McShea MC, and others (2013). Onset timing, thoughts of self-harm, and diagnoses in postpartum women with screen-positive depression findings. JAMA Psychiatry, 70(5), 490 doi
Among women who screened positive for depression after birth and were then assessed by structured interview, a meaningful proportion had a bipolar spectrum diagnosis rather than depression alone, and many episodes had begun before or during pregnancy rather than after delivery. This is why a self help course must not try to tell a woman which condition she has.