In what is supposed to be the happiest time of their lives, they are lost in suffering. That’s what makes postpartum depression so destructive – the feelings of guilt, isolation and hopelessness that overtake a parent even as a source of immense joy sleeps nearby.

That’s also why it so often goes untreated. Among new mothers, about 1 in 9 is estimated to suffer from postpartum depression, but most do not receive treatment. Too often, they’re left to wonder what’s wrong with them.

Of course, it’s nothing the mother does or does not do that causes postpartum depression. Instead, a complex confluence of factors can be involved, chief among them the quick drop in hormones that accompanies birth but also exhaustion, previous depression, family mental health history, medical complications and others. (It can take no more than the latter factors; postpartum depression can occur in fathers and adoptive parents, too.)

But with all the chaos and excitement surrounding a birth, the tendency to hide depression and the general lack of public understanding of it, risk factors and symptoms can easily be overlooked.

What is it like? Amanda Brown, a nurse in central Maine who suffered from postpartum depression and now seeks to help others who are struggling with it, told Morning Sentinel columnist Amy Calder earlier this year, “As time went on and it didn’t pass, I didn’t tell (my family) because I wanted them to think I was strong enough. I didn’t want them to think I was a failure. I remember pleading with God, ‘Please let me love this child.’ I would Google things like, ‘I don’t like motherhood,’ and ‘What if I never love my child?’

“I just felt like there was no way out of this dark tunnel that was never going to end.”

Postpartum depression can last for weeks or months without treatment, and that can have long-term effects on the development of the child and the bonding of the family.

The worst-case scenario may have played out earlier this month in Lincoln, when a mother stepped in front of a tanker truck on Interstate 95, killing herself and seriously injuring her 2-year-old son, whom she was holding in her arms.

The family of Heidi McGovern, who also had a 10-month-old and was pregnant at the time of her death, said she had struggled with depression. In her desperate state, they said, McGovern may have been trying to save her son from dealing with the same mental health problems she believed she had passed on to him.

That is by no means a typical outcome of depression. When mothers come forward with their suffering, it can sometimes be met with fear and misunderstanding that are counterproductive.

But it is necessary to look at the illness in all its forms, so that people with postpartum depression are met with acceptance and treatment, not uneasiness and suspicion.

The first step in that acceptance is to realize how common postpartum depression is. It should be a central part of the birthing discussion, not only in maternity wards, where it is already being pushed to the forefront, but also with friends and family members, who are often the first to see symptoms.

Postpartum depression is also an issue of public nursing, an area Maine is rebuilding after several years of neglect. Public nurses visit new mothers and can help families identify and treat any problems.

Family, friends and medical providers can all help burst the bubble that forms around a person struggling with depression. Maine must make sure they are informed and available so that new mothers don’t have to face it alone.