According to your doctor it seems your pancreas has lost its functionality that is where you require lifelong PERT that is pancreatic enzyme replacement therapy.Your pancreas is unlikely to recover to full functionalty. your frustration feeling will sum up to your problem and make you feel more weak,tired.instead try to see the postive aspect that the medicine suits you as there are some patients who cant take the medicine due to allergy etc.regarding cost you can change the brand under your physicians guidance.you have to have easily digested food,non spicy,non oily, less salt and less sugar food.and timely balanced diet and regular exercise like walking and yoga with meditation will help to improve your situation. these measures in long run may help to recver your pancreas on its own to some extent where you can reduce the dosage of medicines.