Lost in my life

I think you might need to get some professional medical advice - this is the first move and safety net level to check everything physically and emotionally is ok or if there are any areas that can be supported. Exhaustion can be a sign of depression or be a symptom of any number of physiological causes.
The next level is to understand that you are quite likely fed up, depressed and feeling sorry for your self. You are allowed to feel like this, it is just a question of how long you allow yourself to fester. Your mindset is grieving for the loss of a life and post qualification event you thought was achievable. For whatever reason you have lost an opportunity to get up on that step to a different or maybe a better life. Who knows what your reasons were for not getting the required work done, or by achieving the attendance needed to get your Post Grad. Most institutions have a 'cut off' if they have done their best to help you. Regardless that door has now closed.
You can 'sit' in a mire of self recrimination or decide you are going to start the next chapter in your life in a life long adventure. But only you can do this, no one else. You have to be brutal and ask why you didn't get to the bar on your last post grad? Will you just repeat the same mistakes if you do the same all over again. By all means take your disability into account but that can also be a positive. You have to have the motive and the desire to succeed after a knock back. Only you can dig deep and do this. Why allow yourself to be defined by one failure in life when you can try and again and again and again?
Research all of your options. This is what you should do in the 'exhaustion phase' with minimal physical and cost outlay - it is no different going into battle after your unit have taken a good 'pasting' You regroup and think out what your plan is next. Yours is no different. The hardest part of your situation is your head. Dream. Imagine everything you see yourself doing. Don't put any constraints in the way. Visualise yourself doing the things you want to do and believe you can. Then work out how you might achieve these dreams. But be flexible, you may have your heart set on X but half way follow the path to Z - that is the best (and the worst) part of life. Be curious, be malleable in your plans. This is the school of hard knocks. You need to believe in something. Reach out to any online charities or groups supporting your disabilities. Remember your life going forward should not be defined by your failure, your loss, your disability but the achievements you set out to make for yourself regardless. Having the courage to try something is a huge positive, even if you fail. But the bigger positive is picking yourself up again afterwards to keep going and not being afraid to try again. Life is far too short to sit and wallow. You have to grab any opportunities coming your way and make your own luck to find those opportunities. There will be many people out there only to willing to help you. But you need to help yourself first and get your sense of purpose back again. Good luck.