I heard one similarly depressing story from someone who left a well-known and well-liked (here) company, but it's not my story to tell.

So it would be lovely to hear from people who've taken maternity leave, been able to return to work gradually, gained promotions and thrived - can we name those companies too?

OP, I hope your wife finds a good lawyer and negotiates a good settlement at least. In the UK they'd have a hard time avoiding that.