You can start with NeuEve Silk suppositories, using it twice a week. This helps you to relieve vaginal atrophy.
If dryness is severe, you may add NeuEve balm cream, using it a tiny bit (like a 1/2 of a dime size) to the exterior vulva at bedtime daily. One jar lasts 3-4 months.
The Silk level is the starter level. It will help you ease painful sex. After you are on Silk for 1-2 months, you may graduate to the Silver level to gain more lost functions like libido and orgasm, etc.
About how long you should wait to have sex after using the product, you may find this article helpful:
I hope that you will find relief soon.