Welcome to HCM
You are having Diabetes
for more than 5 years,the medicine you are advised is costly,you are right that tis treatment is longterm,and cost of therapy is important.
There are many alternative available of antidabetic which are equally effective you have to find another Physician and get prescription,please explain your condition doctor will help you certainly.
As this forum is not for prescription online as it would be unethical without examining the patient and prscribing drugs.
Good Luck to you.