Before I used to bite(!) my nail because they were always splitting in the ends and breaking off. Now I have been using nail products from Depend, which I find very helping on my nails - you should deffently try this nailstuff out!
This is the products I have been using for my nail routine;
These products have made my nail much stronger and they almost never break anymore! They are much harder and have grown into a nice shape with using my nailfile.