It could mean anything hun, usually the weather plays a big part, nails like vitamin d to keep them strong as we lack sunlight this time of year nails and hair tend to suffer.
The only thing i would suggest taking is the perfectil vitamins, they are fab for nails, also apply a hardner or strengthner...sally hanson do good ones, and in the mean time keep your nals filed short to avoid ripping further down, and look after your cuticles.
If you have had any kind of acrylic or gel applied recently this can weaken the nails, so avoid that and let your nails breathe themselves.....sorry this is such a rushed answer but hopefully it helps.xx