"Life is not a bed of roses" is a metaphoric saying to the expression "life isn't always fair."
I often find myself alone in this view, but I feel the "life isn't always fair" expression is greatly misunderstood. The expression doesn't mean you should cease to fight for a just and fair society; rather you don't always make it, it's the journey/thought that counts. I prefer to use this expression:
"Life isn't always fair, but we should try to make it as fair as possible."
Usually I get scoffed off as an entitled hippie socialist when I use that expression, so be warned, it's ineffective. Still, it's the truth. The snotty "life isn't always fair" attitude displayed by the likes of my generation and their boomer parents have led to the greatest display of apathy and laziness ever witnessed by human kind.
I absolutely HATE IT when people use the expression "life isn't always fair" when I actually try to DO SOMETHING. Hey, before you judge, why don't you get off your fat entitled arse?!