This is a very valuable life lesson. This is not to say that one should never depend on others, just that no one has your best interest at heart more than, you guessed it, YOU!
When I was younger I was what I like to call a chameleon. I just morphed into whoever I spent the most time with. I took on habits I didn't actually like, I pretended to like music that I actually didn't and I pretended to like people I actually didn't like. Just to blend in. I like to think, in my own defense, that everyone has their "chameleon stage". I consider my Chameleon stage to have been a HUGE waste of time in my life. Instead of figuring out what I liked and what I was into I just adopted all my character traits from others and it delayed me figuring out who I really was. What a waste.
I love this quote because we all need to realize that WE know best for OURSELVES better than anyone, and if you follow along with someone else's plan, it will NEVER be tailored to you the way that your own would.