That's a really important topic and I've felt some inspiration to create a topic for it so it could help others as well.
The thing is, most of our anxiety and depression related negativity really comes down to not accepting ourselves. We "need" acceptance from others and we "need" to meet other peoples standards in order for us to feel happy. In other words, we constantly "need" to prove for ourselves that we are worthy. When we get desperate enough to the point where another person's (even stranger's possibly) reaction to us determines how worthy we feel about themselves, then inevitably we will feel bad about ourselves and shouldn't be a surprise for us to experience more and more rejections.
Think about it, if you were a super self confident person who is approached by someone who links their self worth to your response to him (it's not that hard to notice), would you really be fascinated by his company? First, in a way he is trying to use you for his own selfish needs, moreover, it's really hard to trust and get to know the genuine side of such person cause he will constantly be covering up for his all little faults and telling whole kinds of little lies in order to make himself look "better" in your eyes, which will only distant himself further away.
So is it harmful and sabotaging not to accept yourself? It's obvious that it is, right? Now consider this, what BAD would happen if you would actually accept yourself the way you are right now?
Anything.. nothing? What stops you from doing so?
For people who believe in God, the goal should be to accept themselves as a soul, and soul by itself is obviously "worthy" no matter who you are as a person, while atheist can see it as everyone is unique and special, therefore they are "worthy" no matter the circumstances. And again, what are the disadvantages of accepting yourself with all your current flaws?