sounds like you're having a pretty rough time
i dont know much about panic attacks- maybe its worth taking up some kind of relaxation technique such as meditation or yoga?
i can relate to a lot of the things you are saying- bullying, similar dad issues, general loneliness, wondering why the hell you're still alive..
you mentioned coming very close to anorexia? trust me; do not go there. if you think things are bad at the moment, its nothing compared to what it will come to- picture things as they are now, but with even less energy- and losing connection with friends and family because you're paranoid they are going to realise and try and fatten you up. you really dont want to go down that route.
if anyone knew a fool proof way how to be happy that applied to everyone, they would be a millionaire.
you dont just deal with yourself. everything about you has had however many years to build up and you cant just change it in a few hours. all you can do is deal with the specific things that are bothering you at each point in time.
if you ever need to talk, feel free to message me okay?