Hi Barbara, welcome. It sounds like you are able to test your blood glucose (BG) which is great. A little more info would help us
When you say high then dropping really low, what numbers are you getting ? and when are you testing, ie are you testing just before eating then two hours after starting to eat.
Many of us do have to be careful with fruit , it's not only the amount of fruit it's the type of fruit too, berries are often tolerated better, grapes are little sugar bombs, fruits that originated in hot climates are usually high in fruit sugars (sugar is sugar not matter how natural it is )
The best guide to what carbohydrates your body can tolerate is your glucose meter, has anyone explained how to do this ?.
May I ask who is giving you this dietary advise