Sometimes, to make something socially acceptable, you need to present it in a way that most people (even with consumerist leanings) will understand.
Do you know anyone who has had a heart attack or gotten cancer too young? Anyone who died shortly after retirement (or even before retirement) and never got to enjoy their golden years (or even enjoy life, if they kept working and putting off other things until retirement)? By my mid-30s I've seen various sad cases where relying on there being a tomorrow (when you'll finally spend time with your family, pursue your hobbies, take care of yourself, and enjoy life) hasn't worked out for the people in question. If you absolutely must explain yourself to others (besides your wife and kids), this is a very relatable reason. "Seeing ____ get sick/die young really hit me hard and I realized I need to make time for my family and to enjoy my life sooner rather than later."
Lots of people couch their ER as a break/sabbatical or a career change.
For your wife and the house, is this the house you want to raise kids in (so, live there about 20 years) or that you hope to die in (live there 40-60 years)? If #1, part of your plan can be to eventually downsize (release some equity and reduce your housing costs). If #2, you can aim to buy a more modest, adaptable place with future accessibility needs in mind.
The scenarios and concerns you raise are brought up extremely often in this community. Browse for some existing threads to read and you may get more ideas or insights you find useful.