Don't Change!
Sometimes when someone doesn't accept you, or like you for one reason or another, you might think it's you, that if you were different they'd see how wonderful you are. The truth is, that you're who you are, and people either like you or don't. It’s impossible to please everyone. If you try, you’ll always be sacrificing part of You.
The key is to be Yourself. The right person will love that Self for who it is. If you fake who you are to get approval, you'll never be truly happy or at peace. A part of you will always know you're an impostor.
So invite the right people into your life. You'll know who they are because they'll love you just the way you are.
Slipstream
You make a good point. People often sacrifice so much of themselves to be something someone else wants. Faking you're someone you aren't can only lead to disaster for all involved.
Sanatana
It does lead to disaster because eventually the real you surfaces in one way or another.
Evangel
So often people don't truly know who they are. If they have an opinion about who they are, it's usually diminishing. So they easily become someone they'd like to be, or think others would like them to be.