It may be cliché, but it's still hard to comprehend until you reach a life goal and have to ask yourself, "Wait... Now what?"
It's much easier when there's a milestone -- just pick another one. (Graduated? Graduate again!) Then you run out of milestones and have to ask more difficult questions.
Agreed, I find myself the same way. I end up keep asking myself. Is this really what I want in life? or perhaps there's another avenue or path that I could take that would fare better for me in the long term
The real question is one of assigning value to each goal. The valuation changes as do you.
It is easy to get into a local trap of running for a goal you no longer value. It is also easy to get trapped in switching between goals without progress.