Hi there. I hope I can help you out with this. I actually had healthy, long and strong nails for most of my life, but then several years ago I got sick with an autoimmune disease, everything about my health went south, including my nails. They would break off, peel, you name it, they did it. It was difficult for me to accept. Eventually my nails came back, and I swear by doing the following:
#1. get a good amount of aerobic exercise. All that blood flow to your extremities can help the health of your nail beds. I know this made a big difference in my nail health. #2. Fill any nutritional gaps you may have with multivitamins, or vitamins geared toward hair and nail health. When my nails started to bend and get weak, I was religious with my vitamins and I would say in about a month my nails were strong and hard again, #3. Find a good basecoat, I swear by OPI Nail Envy, pricey but worth every penny. Please be aware that their original formula does contain formaldehyde, not good for us but it does make your nails very hard, there is a formula for sensitive nails that is formaldehyde free, it is worth trying. And #4, every once in a while I will take my polish off and for a day or two let my nails go without it. I swear this allows my nails to "breathe." They seem to get a nice healthy boost of growth when I do this. But I am mindful not to clean or do anything that might make them vulnerable when they are polish free.
Good luck! I hope this helps!