Just to give the full picture, you did not quote the proverb, but just half of it, which gives it a very different meaning than if you quote the whole thing.

“Hope deferred makes the heart sick, but a longing fulfilled is a tree of life” is the full quote.

The difference between hope and longing may be subtle, but the thought as to the difference is a world apart.

It's like when people love to say that Shakespeare said "Kill all the lawyers!" as if he thought lawyers were complete crap, but don't give the context, which is basically that if you want chaos in your country, then killing the lawyers is a good place to start.