“No man for any considerable period can wear one face to himself and another to the multitude, without finally getting bewildered as to which may be the truth.” ~Nathaniel Hawthorne
Not only knowing who you are is important, but also always staying true to it. The moment you become what someone else thinks you should be or hide the real you underneath a facade to fit in or appease someone else — is the moment you lose yourself.
On the other hand …
If someone is acting one way, but is truly someone different than they say — in time, the truth will prevail. Take things slow and always seek truth.