How to recover from shopping frustration and road-rage?

Do you also fall victim to utter frustration when hitting the shops and/or driving to/from the shops…..and not to mention parking? If so, how do you get over it?

I just got back from a shopping trip that included idiot drivers going max. 70 where 100 (km/h) is allowed, 2x parking space snatched right under my nose by drivers going in the wrong direction and being bumped in to with shopping trolleys at the DIY shop – oh, and the supermarket was out of my brand of smokes!
Suggestions are SO very welcome!