I am not young nor am I new to therapy, and there are many times I still feel like this, because I have always related to people from a place of fear, believing I will be rejected because I project my parents onto everyone else.
I still have the expectation that everyone feels about me the same way my parents(abusers) did, and used to believe that I was bad, wrong, unlovable and deserve to be rejected and abandoned, and old habit that I have to challenge over and over again. Over time I have learnt that they were wrong and to blame , my T won't reject me, so I have become braver and am starting to learn healthy risk taking, but it has been a very slow process. I still say sorry if I cry, because I feel embarassed and wrong.
Little steps, one at a time, question what you are telling yourself when you feel like this, and talkiing about those beliefs and feelings in therapy can be very helpful.