Goo, the only thing to do in these situations is start singing The National Anthem very loudly at the top of your voice.
Erstwile exclaimer will leg it as he/she now thinks you are a complete and utter lunatic and will most likely avoid you at any and all future family gatherings.
Job done.
Waltzing Matilda, Waltzing Matilda, You’ll come a-waltzing Matilda with me…
Enjoy,
Steven
Good for you, Goo!
With renting, I don’t take more than I need, even if I can afford to. Especially since the money goes right down the toilet anyway. But if I were to invest in my own property, well then I’d make damn sure to finally enjoy some elbow room! Why the hell not? 5 bedrooms for one person?? Right ON. 
Just thought I’d update by saying a few things.
The move went fine, apart from some internet access hiccups.
The house is great, I really like it. Big improvement over our last hovel.
The family member who was such an arse about us moving, tried fishing for an invite to come over and be nosy, before half our boxes were unpacked. Said family member was politely told that there just “wasn’t enough room for entertaining” and that we were considering moving again to “something larger” in six months time. 
That’s just the best thing to have said Goo! Glad the move well and you enjoy your extra space.
Also, I don’t like the implication that you and your husband aren’t a family without kids. Awfully narrow definition of family she has.
I’m not so sure. I’ve heard that large houses have an alarming tendency to roll over when you corner too quickly in them.
3 bedrooms is a big house? my brother is building a 3 bedroom and it is barely 1200 sq. feet.