Suggest Treatment For Vaginal Yeast Infection With Diabetes

Hello, my name is alexandria. i am having a very tough time with what i think is a vaginal yeast infection. I went to the health department about six months ago was told it was one and given a diflucon pill. But, it didn t help. This has plagued me for nearly three years. I have all of the symptoms of a yeast infection, but it burns so badly that I have to sleep with my legs straddled out. it hurts up towards the top of my vagina, not at the cervix opening. I have a lot of white discharge. i am married and have had the same partner for four years. so i don t think its an STD. please tell me something I can do. Could this be related to diabetes? I am on 1,000mg metformin, I have taken it for almost eight years. Could I need to be on insulin? Please help I am so uncomfortable. I unfortunatley have to take a narcotic pain pill just to sleep because it burns so bad. anything you can tell me would help!! Thank you so, so, much!! Sincerely, Alex Clement