I think she emerges as an unhappy, isolated, rather tormented person in The Wild silence, certainly, though whether you'd put that down to a MH crisis, guilt at past misdeeds, worry about Moth's condition, fear that the omissions and half-truths of TSP would catch up with them after it was published, I don't know.
What always interested me about TSP is how angry, bitter, self-righteous and emotionally untidy it was (compared to say, other recent high-profile nature-ish memoirs like H is for Hawk and The Outrun). It's just such a misanthropic book! With a few exceptions, other people are almost all awful. Which could of course be projection, or self-justification. Maybe one of the things that interests me about the Observer allegations and RW's 'rebuttal' is that being able to fill in some of the omissions actually makes way more sense of the first two books.
She ascribes so much to her longing to hide away and commune with nature, and to this being a lifelong thing, but in fact it never seems to make her particularly contented. It seems more like the self-soothing of someone who can't cope well with other people. Or for whom it's easier to think other people can't be trusted than to look too hard at her own decisions.