Hey..
My opinion is people normally give such response because they
want to make you feel guilty and help them.
There are people who take things for granted.
When we chose not to help them, they would say we are selfish
and unfriendly (i got this kind of comment sometimes).
However, if you hold your stand, one day they would respect you
and understand you.
You dont need to explain yourself that much.
Cos some people don't deserve to tell..
*cheers*