Hi,
Well, I went thru some life stuff and believe me, not everybody will like you, appreciate you and you can only grow thick skin. F*** these girls. Love yourself, your body and look at yourself in positive way. Do not let these toxic naysayers diminish your light and value.
Its psychological manipulation what they do to you and exclusion. They possibly wanted to use you to do job, and now bcuz you stood up for yourself, they are punishing you/trying to guilt trip you into apologising or simply, they want to bring you down and make you fail in life/academics. Ppl are cruel. Better grow thick skin.
As for memory issues, concentration issues, physical symptoms-go and see doctor. No shame to seek help. Do not suffer in silence. Is it sudden occurrence, long term issue or did it start after friends dumped you? Worth checking for ear infection.
As for own shadow distraction/lack of goal-sounds like anxiety but I am not dr so can't diagnose you. Its common in life to not have goal, lose goal, lose interest. You live many lives in your one life.
I had a job for 10years and now, I work part time and I struggle with mental health. I failed Uni and I am in my 30s. No idea what is next. I will recommend what drs/kind ppl recommended to me-journalling helps. Write it out. Anger, feelings. Career ideas, possible goals. What you liked, like. What would you like. its just some ideas but you can write, whatever you want. If you are ashamed of own feelings, then write and tear the paper.
Except journalling, you can seek some online resources for mental health. Nhs sites, listening place website.
Also, you can go to GP and ask for therapy but due to own experiences, I know not every therapist is professional. Good therapist will help you to address concerns, form sort of goal, and will be transparent how many sessions you have and what they can do for you in limited time. Be strong. Be resilient. Life is tough.