I would recommend that you start back at the beginning and re-train her. Forcing her to hold still is just going to guarantee ongoing battles and deteriorating trust between the two of you. My cat was feral when we started this process and now he's pretty good about it. It can be done in a way that is gentle and respectful of the cat.
Start with desensitization practice as Veronica suggested. Find a place that will always be the testing place. Somewhere with good light and a calm feeling to it. Take your cat there several times every day. Gently hold her in place, rub her ears for a second or two, and let go. Give a treat at that place. At first she might run away as soon as you let her go, but she'll eventually come back for the treat, or you can calmly retrieve her and put her back in the testing place to eat the treat. In a day or two she will learn to wait for the treat. Don't ever take the treat to the cat. Only give a treat at the testing place. Consistency is essential here.
You will need to do this several times every day to train her.
Once she's getting used to that, start to lengthen the amount of time you hold/rub her ears. Always give a treat. If she will let you, also give lots of love and chin scratches and head kisses.
Then start to warm her ear before the treat. Warming the ear makes a huge difference in getting a test quickly and easily. Some people put warm water in a pill bottle and hold it to the ear. Many of us use uncooked rice in a little sock or felt pouch. This can be warmed in the microwave and then held gently to the ear. Figure out what you will use for warming and add this into your training routine.
Warm the ear, let go, give a treat.
Then start going through the motions of testing without the poke. Have the meter there, put in a test strip, touch her ear, let go and give a treat. If your meter beeps either turn off the beep, or let her get used to hearing it.
Finally, start with the real tests. Have the test strip part way into the meter so it's easy to activate it as soon as you have blood. Warm the ear. Poke, and milk the ear to get a bead of blood. Do the test. Let go, give a treat and lots and lots of love.
There will still be good days and bad days, but if you go through this process carefully, calmly, and gently, your kitty will learn to cooperate in the process.
Our kitties read us, so if you are anxious or nervous about this, your cat will be too. It communicates to them that there is a reason to be afraid, and therefore they will fight. Make sure you are calm and confident first. If you need to, put on some music or the TV, or sing a song quietly to keep yourself at peace.
With a difficult kitty, this training process will take a few weeks. You need to be consistent and do it every day, a few times. Once in the morning, once mid-day, once in the evening, and once before bed is ideal, but whatever works for your schedule.
And please keep posting and asking for help. We have a zillion tips and tricks to help you and your kitty learn to make this part of your daily routine. My kitty was a ferocious biter when we started and this whole process has made him quite lovey and gentle. I never imagined stabbing him four times/day would actually improve our relationships, but it has a million times over. Like I said, he still doesn't love the tests, but he cooperates, and that's enough so that I can keep him safe.
My cat will never be one who lies still and purrs while we do the test, but he keeps his wiggles to a minimum and allows it to happen.
