Struggling with this too after 3 weeks of trying everything under the sun at bedtime dr put me on a pill before bed.
the fasting blood sugar is actually the hardest to manage in pregnancy.
You could try eating a protein / fat snack (rather than carbohydrate), at bedtime.
You could also try taking a walk after dinner (may help reduce the insulin resistance).
Ultimately though, you may end up needing medications to get your sugars on target.
Best Wishes to you and your baby.