If this all sounds horribly familiar you'll also probably know that getting your wing mirror replaced is a highly annoying task - you can't drive without two fully functioning mirrors but its such a small thing to go and fix, usually with a large garage bill attached.
The good news is, a trip to the mechanic is probably not necessary - unless you've done some serious damage to the wing of your car you can probably find the replacement parts you need on-line at a bargain price. For instance, if you've cracked your wing mirror glass but the rest of the mirror is fine, you can avoid a full replacement by tracking down stick-on wing mirror glass, which you simply need to place on top of the original glass using an strong adhesive patch. if the mirror is beyond redemption you can also find replacements on-line for almost every make and model of car, and usually at discount prices.
It's also worth remembering that car wing mirrors don't just have to be a functional item on your car - if the thought of replacing a broken one is depressing you, look at it as an upgrade: shop for a wing mirror with a chrome finish, or choose a carbon fibre model to toughen up for the next potential bump!