laura, is your goal to get her off of insulin?
if so, you really need to learn to shoot lower numbers. experienced people will shoot everything over 50ish if they are going to be home to monitor. if it makes you nervous, gradually lower the numbers you will shoot and "practice" shooting lower. If you won't shoot anything under 200 now, start with shooting everything over 150. Then 100, then 75, then 50.
That's what Tight Regulation is - we try to keep a cat's BG's between 50-120 so that their pancreas will heal if at all possible, and they'll go off of insulin. If their pancreas isn't able to heal, keeping them in that range is protecting their body from the damages of high blood sugar.
Lantus works best when the numbers are lower. You won't see the gigantic drops that you see when you shoot a 300 or a 500. Mom Mom will feel better if her BGs aren't going up and down by 300 points every day.
Look at today's posts for Oliver, Trey, Dimitri and Zack - look at these cats' spreadsheets and notice the preshot numbers. Look at the preshot numbers that they shot that are less than 100 or so and look at what happens in the rest of that cycle. These are all newly diagnosed cats, just like mom-mom. When they started shooting lower preshot numbers, the high numbers on the spreadsheets basically disappeared.
Numbers over 50 are completely safe. Numbers in the 40's mean take action, give some carbs to bring up the BGs. You don't have to panic about these numbers.