Mate, I'm a bit tougher on the extended family and unwanted advice. If he don't like it then GTF out of the house and go home to his paludrin. My old man doesn't like my wife of 17 years so I haven't spoken to him for 10 years after telling him to get out. MY choice. This woman is more important to me than anything else. We discuss what happens in our life together...no-one else gets a say.
20 years in the Army in the most dangerous crap you could imagine from live fire assaults, explosives, rock climbing, parachuting, abseiling out of choppers and a bit of the 2 way shooting range and I end up half crippled from a jogging slip
Live what you can of your life IN CASE it goes to hell.
I often can't race, let alone drive properly or safely due to nerve pain. My passions for cycling and refereeing Rugby Union go unfulfilled. Work is all but impossible due to the drugs and chronic pain affecting my memory and concentration, added to an inability to sit comfortably unless in a recliner.
I've had a pretty fair chop at life, probably lived enough for 2 or 3 but I've got things to do yet so I'm justifiably bitter at such a pathetic incident spoiling things.
Talk it over with the wife, confront the F in law with reality and do what you your wife think is best.