The hardest thing to do is to hang on to the things that are the best. They are the things that in our despair we can snarl at as if they are enemies. Their beauty pains. Hanging onto these things may possibly cause some to consider you naive at best and maybe a bit batty at worst.
You may be considered childish if you hang onto those things that are beautiful, like hope combined with action, like human goodness, kindness and compassion. It's not that those things have failed; it's that they are routinely squashed by the imposed system of artificiality we have swum in from the day we were born and by blind and stupid people who want to take shortcuts.
Go ahead and consider those who hang onto these hopes childish all you want, if it helps you in your despair. Just remember that those who hang on also despair. Hanging on to a vision of the best is nothing to do with childishness. It is not a weak state though it may appear that way when you've fallen into the despair pit.
In actual fact it is the ultimate in fucking strength. It is not childishness ~ it is childlikeness. Something as beautiful and fragile as gossamer. Even if the whole civilisation was collapsed around my ears, after my despair I would reserve the right and the pleasure of continuing to muster up as much of that as I possibly could.