Training in relaxation by an experienced practioner in the field can be helpful. Diet, without it becoming a fetish, can also contribute to a feeling of well-being. Again, control comes into play. Patients, by careful observation and systematic recording, can often discover exercise regimes, types of food, and daily activities, which particularly suit them. Mentally, each person has a choice of options and priorities within the restrictions imposed by illness.
Priorities inevitably change.
You might want to consider evening classes or an Open University course which has the advantage of giving ample time for study. Planning for the future is a challenging experiment which can be best carried out by the individual concerned - usually with the help of family and friends. Satisfying activities may then appear to generate energy and help to deflect attention from irritating symptoms. Illness does not strike in isolation but affects families and friends. In the field of head injury, this key role has begun to attract proper recognition.