I think u could be having depression and bulimia nervosa.
Both conditions are treatable . If you ever had manic or hypo manic episode it is better to be on a mood stabilizer like lithium and take it along with an ant depressant like Zoloft. For past history of mania antidepressant alone is not advisable
You need to talk to a psychiatrist soon
I'm sorry and yeah it sounds like a genetic thing... If your mom doesn't understand talk to a friend/teacher/doctor/whoever you care about. You are good enough. Please try to get help for your eating disorder too, I know it doesn't feel like it but it does cause life-long side effects. Please, if you can, talk to a professional, it is a medical problem and there is really helpful meds, not to mention just talking can really help. Message me anytime and I really hope things get better.