I dont reckon you have anger management issues.
Its plain and simple. The guy next to you is an inconsiderate w@nker.
Nothing more nothing less.
It has nothing to do with you. HE is a w@anker.
I find myself frustrated by these ignorant fools who think rules only apply to others.
Park half on his site and when he grumbles say "oh sorry mate, thought we were sharing...."
Just make his life difficult, but remember you make to need to back up your actions if things get ugly.
And AGAIN. You're not the one with a problem..... He clearly is.
(On a side issue) I had some grief with a w@nker who decided to park his boat right in front of my site which had a beautiful view to the lake. He left just enough roof down the side for me to squeeze my car in.
When I approached his mob nobody seemed to know who's boat it was.
No problems, I just hitched it up and as I started to drive away, the bloke who claimed to not know who owned it, suddenly remembered it was his.
Probably a good thing as I was going to park it in KFC's drive thru.
Some people are just shouldn't be allowed to breathe....