I’m very sorry that you are having such a tough time. With all that is going on inside of you, it’s not surprising that you are having trouble concentrating in school or maintaining relationships.
Sometimes people have an exceptionally difficult time adjusting to a major change. We don’t know why. It may be a matter of temperament or a function of how much support a person has when life is in upheaval. It doesn’t help to blame yourself for not being able to cope. What may help is understanding your problem and doing something about it.
An adjustment disorder is precipitated by a known event and is characterized by more distress than what would normally be expected from such a change and significant impairment in social or academic functioning. The symptoms you describe would add “with depressed mood” to the diagnosis. An adjustment disorder is considered “chronic” if it goes on for longer than 6 months.
On the other hand, adjustment disorders rarely include suicidality and bulimia. It may be that you have moved into a clinical depression. A person with major depression has 5 or more of these symptoms: Sadness and irritability most of the day, every day; Diminished interest in activities; insomnia; Weight gain or loss; Lack of energy; Feelings of worthlessness; Difficulty with concentration; Recurrent thoughts of death or suicide. Eating disorders often are associated with the diagnosis of depression.
Regardless of the label, you need more help than you are able to give yourself. I strongly urge you to go to a mental health professional for an evaluation. You may need some medicine to give you a lift so that you can benefit from talk therapy. There is no shame in needing a crutch when you’re limping. There’s no shame in needing some medication to help you when you are too emotionally distressed to help yourself.
I’m very glad you wrote. Three years of suffering is far too long. Please follow through now and get the professional help you need.
I wish you well.