HELP FOR LOVEY LOU

OK, Here goes....

My Cat Lovey Lou, 12yrs old was diagnosed with Diabetes on 2/1/17 .
She was excessively drinking water and extremely large urination. I had her on dry food only at the time of diagnoses. Her level was at 560!!!
I made her an appt for a glucose curve for the following week 2/9/17
In the meantime, I did a ton of research and I put her on a can food diet with the best I could find in my area 13.5% protein. I was given a prescription for Glargine, but was unable to afford it before her curve that next week. I ended up buying the Vetsulin.
After her first curve, my vet set her insulin dose at 1 unit in the morning and 1 unit in the evening. The vet told me that they weren't getting her level down as much as they wanted during her curve but it could've been caused by stress and just the initial insulin dose. I started Lovey Lou's insulin that evening and continued the canned food diet (no treats). Her next curve was scheduled for 2/23/17. I didn't see much improvement from her her first 2 weeks of insulin injections. She was still excessively drinking water and large amounts of urination.
The day before he next curve appt 2/22/17 - I noticed she was having back leg issues.
When I dropped her off on 2/23/17 for her second glucose curve, I told the vet about her issues with her leg.
Her results on her curve showed no progress, and her levels were still very high 435-460. The vet changed her does to 2 units in the am and 1 unit in the evening and explained that the leg issue is due to neurapathy. She said it's just a part of her diabetes and is a result of her her levels being high.

Well as of yesterday 3/1/17 - Lovey Lou is doing worse. She can barely walk and still drinking a ton of water/large amounts of urine. Now both of her back legs are causing her issues. She is howling and sounds like she is in pain when she tries to walk. She won't sleep with me or even leave the room that she has been in for the past 24hrs. I have seen zero improvement as of day one and she seems to be getting WORSE. It's terrible watching her try to walk and I feel like she is suffering. She even bit me! She has never been agressive or mean and I know she must be in pain =(((
I called the vet and they told me to bring her in right away. I took her in this morning 3/2/17. My normal doctor that has been working with Lovey Lou was in surgery and I had a different doctor today . The doctor felt around her stomach, back end, legs and tail. Then put her down on the ground to see how she was walking. Lovey Lou of course was super stressed out and wasn't showing the same painful, stiff symptoms as she did at home as she was trying to get back in her cat carrier and was very scared. The doctor did a glucose test and it came back at 460!!! She said there is nothing they can do for her right now and that I should just keep her on the same dose of insulin until next week when they do a fructose test. ???????? I asked why she is getting worse? The vet didn't give me an answer and said just keep doing what you are doing and see if she gets any better.
I was very frustrated and brought Lovey Lou home. She hasn't moved more than a 2 foot radius since we got home. She can barely stand and howls and meows loudly when she tries to walk. .......She is laying right in front of her water bowl and won't get up. I brought her some food and she took about 3 whole mins to get up and eat, but sat down to eat and then drank a ton of water. She is now laying by her water bowl and hasn't moved for about an hour.
Why is she having such a hard time??? Why isn't the insulin helping??? Why can't she walk??? Why won't the vet do anything???? Is she in Pain???
I'm soooo frustrated and I want to help her.... but don't know what to do. Her next appt is 3/9/17 - I don't think I can handle watching her suffer like this another day!!! Should I call my vet back and ask to speak with my original doctor???? Any help, suggestions would be greatly appreciated.
KS