Lordy, no wonder the planet is draining of fresh water with you lot around!
Sports bra....clean everytime.
Other bra....until I sniff and it may vaguely smell. I mean, come on, unless you have a major hygiene problem (sweat excessively) or are bf, you do not need to change everyday surely?
I change pants everyday, and socks. Other clothes get washed when they smell or have stains. Jeans have lasted...lets just say, a very long time..between washes before. I use the same system for dd. Occasionally there are days where she does not leave stains on her clothes...so I wont wash them.
IMVHO I think doing otherwise is v wasteful; on a par with putting 4 items in the dishwasher and letting it run.