Life is a journey
This metaphor might be interpreted to have either a negative meaning or a positive one. The negative meaning may be “There is no turning back” and the positive one may be “Enjoy the life”. Which interpretation is correct?
In principle, one might think life is a journey is simply neutral, but in practice it’s almost always used in positive contexts.
Sometimes the positive nuance is direct – either with the implication that life is an interesting journey (in and of itself), or that it gets you to somewhere good (you’ll go to heaven eventually).
But often the positive slant comes from using it in contexts where the good thing is you’ve got past some bad point within the metaphorical “journey of life”. Which wasn’t entirely negative, because you’ve learnt something (so if you reach a similar point in the future you’ll be better equipped to handle it next time).
If you want to use this metaphor in an explicitly negative context, you could say, for example…