After she finishes Hogwarts - properly, which takes another term; NEWTs sort of got lost in the shuffle after the battle - Padma goes to America.
Everyone in the castle, even some firsties who were younger members of wizarding families, is a right mess. People stop and look for someone who's not there; people flinch every time a staircase creaks; people avoid certain spots on Hogwarts grounds without discussing it. But no one can talk about it, and Padma needs to spend some time not surrounded by ghosts.
Besides, it turns out that American society is more fully integrated when it comes to magic, and American universities know what to do when handed Hogwarts credits - something that can't be said for their British counterparts.
She starts her time in New York with a vague idea of doing a thesis on Indian magic (the way her grandmother does magic has always fascinated her), but it turns out to hit too close to home. Her mother knows a lot of the same spells - well, knew them; she went down and took five Death Eaters with her, and the Healers at St Mungo's don't know if she'll ever regain her sanity. She needs something she doesn't have any strong emotional ties to; she needs a Muggle-- non-magical subject.
The Intro to Psychology class she registered for on a whim turns out to be exactly what she needs. It also hits close to home, but in a different way; reading about how people react to the sort of things she's been through helps her sort through her own reactions (her post-traumatic stress) and start to see the joy in life again. Rather than any magical subjects, to the great surprise of people who know she came over from Hogwarts, she makes the subject her major.
She's almost tempted to apply for a job and stay on in America for good, but then her steady stream of letters with Neville bears unexpected fruit; he says that talking through things with her, through the lens of what she's been studying, has helped him immensely. He says he wants to talk to her in person, but the Healers have had some good news for him, after the death of the woman who tortured his parents (it's unlikely they'll ever make a full recovery, but they've managed a few coherent sentences now and again, more than Neville's ever heard from them that he remembers), so he feels the need to stay.
Padma realises he's not the only one who could benefit from having a therapist - a therapist who's been in the exact same boat as the vast majority of the people she'd be treating, to boot. It's not a job that anyone who hasn't been to Britain could do, no one else has left the country long enough to get the training for it, and they certainly couldn't ask a Muggle therapist to take all of this on; while the war impacted everyone in Britain, they wouldn't have the context.
So when she gets her degree, she packs up and moves back to London. She rents a room in Diagon Alley - next to the Wheezes shop, which isn't as terrible idea as she'd thought it might be, at first - and Neville and Luna help her spread the word.
Maybe things will reach some sort of equilibrium again after all.