As I said at the time …
From those last surviving aunts, piece together what you can from what memories, photos, and documents you can collect. Maternal sides, especially, can fade from sight, even within the recent past. These personal histories can be far more revealing than those of public figures we usually hear. Especially important is recording the negative findings, as well as the positive.
Look, too, for medical markers. The depression, for example, could arise in genetics or social patterning. For what it’s worth, I suspect there’s a strand of it in my Dunker ancestry. The Hodgson/Hodson/Hodgin males, meanwhile, seem to die largely of heart diseases, probably a consequence of a high cholesterol North Carolina-style diet.
The past lives on, one way or another. It helps to discern its presence in defining your own values and actions.
Jnana's Red Barn 
Regret at not having asked more questions seems to be a life stage.