If HD changes *anything* - sailing lessons, book club, his finances, his fathering, his housekeeping, or FITB, she is going to take it as nothing more than a response to the "sex thing" and any attempt by HD to raise his head above the status quo is going to send her over the edge.
IMO, sex should be taken totally off the table at this time.
So much of what HD has posted regarding his wife has been her reactions to falsehoods & half truths from him. He has chosen to lie to her on many occasions rather than stand up for himself in a mature way and deal with her anger at the time.
He has tried to jump through numerous hoops over the years, but those actions don't deal with what I see as a major root cause of their relationship disfunction.
HD needs to start respecting himself enough to *be* himself, unapologetically and likewise he needs to earn back her original respect. The relationship is not going to change based on more words or more acquiescence on HD's part. It's time for calm, firm, planned action.