Relax man, these things happen everyday on the roads. But from
what you described, cutting in and out, tailgating like crazy,
playing games, its only a matter of time for such drivers before
its game over.
I seldom see people nowadays cutting in and out unless there is a
big time hogger and the path is clear. To those who like to
tailgate others, pls consider this: if its peak hour traffic, even
if you get the front of you to yield, does that make any
difference? You have another 500 cars in front of you. You want to
keep doing this until you reach home? Everyone also want to get
home fast right, not just you. Just follow the convoy and you will
get home safely.
Even worse are those who tailgate others then once they get pass
they slow down to the same speed as the car they just
overtook.