Viewers know that Lee has been struggling with the disorder for some time now, but doting mum Linda is horrified to realise just what her son is going through.
Linda's husband Mick recently took his son to the doctors – but the soldier has so far refused to take the medication prescribed.
When Linda returns home from her holiday with Elaine, Mick will tell her exactly what's been going on.
But there's a possibility poor Linda will partially blame herself, after everything the family has been through following Dean's attack on her.
A spokesperson from charity Mind has confirmed EastEnders has been in touch with them to ensure Lee's storyline is as authentic as possible.
They told the Daily Star: "We are grateful that EastEnders are tackling the issue of mental health in front of such a large audience.
"For some viewers a dramatic portrayal is the first time they've been exposed to mental health problems and, when done well, soaps can be a tremendous tool in raising awareness, challenging attitudes and helping to dispel myths."
Will Linda be able to save her son? These scenes are set to air next month.