I had an insulin-dependent cat. She lived a relatively long and very happy life, and getting a little needle-stick twice a day for ten years didn't bother her in the least. She lived to be fourteen, and in the end it wasn't diabetes that took her away, but cancer. Please don't fear that a diagnosis of diabetes is a terrible thing for your kitty; it's serious, yes, but not a tragedy.
As for the injections, my Holly often didn't even notice them. More than a few times, she'd be sleeping at the foot of the bed when it was shot time and she didn't even wake when stuck. Believe me, you get expert at delivering a shot of insulin in a very short time.
Insulin and needles aren't cheap, but please don't re-use needles if you can afford not to. A fresh needle is super-sharp, but after even one use, they are blunted a little and can cause pain. Also, there's a risk of introducing infection. If finances are an issue, your vet might be able to work something out with you on prices since you'll be a long-term buyer of the products.
Give Meagan a lot of extra petting and love. While the shots don't seem to hurt them, cats who have a lot of medical procedures done to them can get kind of standoffish about being touched. It's understandable, and I think I'd feel the same way if I had to have a lot of tests run. Snuggle her often to remind her that people-touches can be friendly too.
My kitty felt SO much better SO quickly after getting her on regular insulin, it was amazing. I think you'll find the same true for your girl once she gets on a regular schedule of shots. All my best to you and your kitty!
