There's the idiom sitting on the fence (sometimes said as straddling the fence).
This idiom is often used to describe someone who is having trouble taking sides in a controversial issue, but it can also refer to someone who is simply having trouble making a decision about something.
Which laptop are you going to get?
I don't know - I'm sitting on the fence.
Phrase Finder defines it as:
sit on the fence (Figurative) not to take sides in a dispute; not to make a clear choice between two possibilities; to delay making a decision when you have to choose between two sides in an argument or a competition. (Origin: the image of someone straddling a fence, representing indecision.)
You can read a few examples usages at this website. Sometimes the expression is used negatively, though. Wikipedia mentions:
"Sitting on the fence" is a common idiom used in English to describe one's neutrality, hesitance to choose between two sides in an argument or a competition, or inability to decide due to lack of courage. This is done either in order to remain on good terms with both sides, or due to apathy to the situation and not wanting to choose a position they don't actually agree with.
Another word you could use instead is undecided, or torn:
Which laptop are you going to get?
I don't know - I'm torn.
Collins defines this word as:
torn (adj.) divided or undecided, as in preference ⇒ he was torn between staying and leaving
The word torn implies a reluctance to choose because there are aspects of both possibilities that are equally appealing (or unappealing).
Yeah, it does have a slight negative connotation. But it's not that voice suggests loudness.
Whenever anyone makes a point of distinguishing between saying something and thinking it, one or the other is being criticized, if only by implication. q.v. "You're just saying that."
The phrase "to voice the opinion" is a deliciously subtle example, because it contains within it the distinction that someone both had an opinion and expressed it. It is otherwise a synonym for "said" or "expressed" or "opined" or "suggested" or "proposed":
User123456 in several comments on meta recently proposed that creation of a tag should always be discussed on meta first.
So the choice to use the idiom "voiced the opinion" is significant. It has a chilliness to it. It doesn't make plain exactly what the complaint is, but has a slight asperity to it, as if it were a mild version of "felt the need to tell us".
Best Answer
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...