hi Heather... you do not need insulin unless you don't produce your own insulin. I know some docs use it to get quick control of sugar levels that are too high. Your sugar levels don't sound like they're too high to me... they're in normal range.
For me, I insisted on diagnostic tests to be done again in 2010 as they had me on oral medications for about 5 years and they worked well for the first couple of years and then I noticed my sugar levels weren't so great. I told my endocrinologist that I'm sure I was taking placebos and that something is wrong. I had been on a few types of drugs and dosages as well. I never did tolerate metformin either, even though they kept me on that for 5 years.
The results for me were the GAD test was negative to show I had type 1 or type 1.5, so I definitely still had type 2. The c-peptide test came back in the red showing I no longer produced sufficient insulin. My endo said that I now need to be on full time insulin therapy as no amount of oral meds would work when I don't have sufficient insulin of my own.
I would suggest that if things are working, to keep doing what you're doing. If they're not working, try something different. Don't be afraid to ask for the diagnostic tests to be done again because type 2 is progressive for most of us. I've been on insulin since 2010 so I managed without it for 12 years.
I wish you the best.