After 39 years, am now insulin resistant

Over the last couple of months my bs has been spiking, not just after meals but all the time. Have adjusted my basals from 12.3 units daily to 17.50 a day. Had tried Metformin before, but wasn't really noticing any difference. Now this past week, my sugars have been a bit more stable, Dr. said go back on Metformin, changed bs goals, changed correction factor. I also can't always tell when I'm low, so the other day when I was on the elliptical I fell hard. In 39 years of having D, that was the first time I cried. I'm feeling so overwhelmed. After all, I'm not obese and I workout quite a bit already. My Dr. said she has other T1's on Metformin, not sure if it helps them or not....then why does she prescribe it for them? And why for me? So, I've decided she's an idiot, and after about a month of decent readings, I will stop the Metformin, and see if its working for me or not. According to her, there's nothing I can do for IR. I just needed to rant a bit. Not sad anymore just more determined to get my sugars better, whether that takes a little insulin or a lot. Just worried about weight gain, as I know insulin makes you gain weight.