Pushing a boulder uphill is read as relentless effort with little visible progress. Dream books link it to an endless task, and to the question of why you keep at it.
Where in your waking life have you met something like this lately?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.