Do you have any goal about yourself to achieve. ?!!! Whatever you do for others or because of others or to to prove for others will.all.land up like this. If you can consult a Psychologist and discuss your past and wishes of your future may be you will get a clarity.

What you need to do is pace yourself. Don't spend so much time or energy in one particular activity that it not longer seems appealing to you. Keep a fixed schedule and  limited time for all your activities. That will help you retain interest in them. Set goals and tasks that need to be completed.Keep a reward system for yourself for when you achieve them. Doing this will encourage you to work towards the goals. If you find yourself having no interest in anything, it may be a sign of depression. In that case you need to consult a Psychiatrist.