Sometimes those we trust and care about are the ones who try to break our confidence.
Friends, lovers don't always mean to harm us but sometimes jealousy and insecurities can play a big role in our relationship with them.
Sometimes when someone says something to you about your personality and character it might be true. You should take it as an opportunity to reflect and improve yourself.
Other times when someone says something about you that sounds completely insane, take a step back. Reflect on how they feel about themselves and if what they are saying about you is something that they feel threatened by or wish they had.
Sometimes bitterness is a knee-jerk reaction from people who feel inferior to you in some way. I am not saying this makes their love for you any less or that they don't wish you well. I think maybe sometimes their insecurities get the best of them and they don't realize that they are hurting you with their words and that their words might leave a long-lasting scar on your soul.