This might be kind of long but I actually took an online course/book on social anxiety which specifically addressed how shame affects anxiety. The book broke shame into two categories; regular shame which makes you feel ashamed of an action and toxic shame which takes over your life and makes you feel ashamed of yourself rather than the action, leading to feelings of inadequacy or despair.

So because of this toxic shame, you isolate or withdraw from people and focus on all the parts of you that you don't see as "good enough", which tends to lead to depression and feeling that you have to hide your perceived defects to avoid rejection from people. Examples of this might be hiding your "true self" (your opinions and interests) or fear of intimacy with others. Basically, you are hiding your personality (think of how you might act when you're relaxed around friends) which is why it might be difficult to form new relationships.

In fact, the thing you feel ashamed about really doesn't matter. This toxic shame just tries to hook onto something in your life and make you think your short, have big nose, shitty personality etc. No one saw themselves as ugly and then became anxious, the shame came first and distorted how you perceived yourself. Negative environments are a huge initiator for toxic shame like abusive, uncaring, or overprotective parents. Also, school environments where you may have been called names and bullied.

Took me a long time to realize that none of that shit mattered though. No one's life is really that interesting, Facebook isn't an accurate representation of how people live their lives. And there are people much uglier than you that have got the life you want. I think TIME did a poll not too long ago where women rated confidence in a man as far more attractive than looks. Anyway, I'm not sure what my point was but I hope this helped someone.