@OrangeStapler
Yeah YANBU. As a few pps have said 'oooh ya don't wanna know!' and then grin! 
Some people are nosy gits! And feel it's OK to ask intrusive questions.
DH went part time at work several years ago, (26 hours a week,) as he had had enough of full time work. And after 40 years full time he has earned his stripes! (I work 24-25 hours a week.) We have no mortgage and no children at home and have low outgoings, and we have done everything we wish to do in our lives, so don't need masses of money, and we are comfortable.
Several times he has had someone at work say 'I don't understand how you and Starling manage on two part time wages, with a nice house, and a '17 registered car. ^^ 
And ^^ 'are you two OK?' DH is like 'what, yeah, why?'
'Well.... I hope you're OK financially.. ya know with you both being part time...'
Nosey fuckers!
How dare they try and nose into our bloody finances?! He tells them nothing. Just says 'it's really none of your business.'
Also, my friend who is 57 has not worked since the age of 51, as she has a chronic illness, and she is unlikely to work again. She has had several people (including an ex colleague,) saying 'are you not working yet?' and generally quizzing her as to why she isn't working. She has started saying she is retired, and one woman said 'don't be so stupid. You can't be retired this young,' 
Like my DH, she has earned her stripes. Worked 35 years, raised 2 kids, and has only stopped work because of illness. She hasn't told most people about her chronic illness though, as it's absolutely fuck all to do with them. Still people ask.
And women roughly her age seem to get extremely annoyed and irked that she doesn't work, and hasn't since she was 51. Seems to really irritate them for some reason. 