Yes it is offensive. That doesn't mean that is not true (I don't believe that it is true, actually.)
A more effective statement, given the first statement, would be,:
"Life is shit, refuse it."
"Life is shit, forget it."
If you do not want to be so offensive, you could use 'crap' instead of 'shit'.
I hope your day isn't going quite as badly as that statement implies, by the way.