Re: Medical history
Definitive medical advice can only be given by a qualified service medical examiner, once in possession of your fuller medical history.
In order to manage realistic aspirations, as you may expect, a history of self harm can influence the decision with regard suitability for service due to the duty of care regarding the wellbeing of the individual expected to work under extreme duress in an operational environment and indeed those who may need to rely upon them for their own wellbeing as part of an effective, cohesive fighting force. The rough rule of thumb is the individual needs to be several years clear of any remedial treatment and a history of repeat incidences indicate a significantly higher likelihood of future recurrence - beyond that, all we can advise is each person is individually evaluated on a case by case basis.
Best of luck.