Buy a DIY gel polish kit. V hard to bite through and your nails will look good whilst growing. It is a bit of an outlay but you will get 20 manicures out of the kit. Then you have the lamp and just have to buy polish in future here
I also was a biter for several years (more than 10), and now I managed to stop (it's been over a year ). Here's how I did it. First I had some gel nails and had them for more than 2 weeks. Then, when I got some nails of my own, I started to ALWAYS paint them with brightful colors. Everytime I felt like biting them, I looked at those bright colors and it reminded me not to do it. But my nails always have to be painted (even today)! Well, it works for me!
I bit my nails until I was 37 (August 2009). Got so fed up with them that I had gel nails put on. Had them removed after 3 weeks and my nails had grown underneath, so I had a manicure to make my hands and nails look lovely, then have polished them pretty much every single day. I still occasionally nibble the cuticles but not the nails.
The only problem is that I am now a total nail polish addict!
I find that my nails are quite brittle and break easily so I still find it difficult to keep them all the same length. I had gels and tips put on 3 weeks ago for a special occasion as my nails had all broken off and I wanted long talons (painted black with bright red tips. Chavgothtastic!)
Unfortunately they break right at the nail bed, because I used to bite them so short.
Am having the gels taken off today because my nails have gown loads! very excited to have long nails back.
Oh, and I have also been taking the Boots own brand of Perfectil skin, hair and nails supplements, which has helped. I also use Sally Hansen Miracle Growth as a base coat.
I have very weak brittle nails and have found the best way to get super strong nails is to eat a couple of squares of jelly every day. You notice the difference about 3 months later. I always start it then give up then 3 months later get really strong nails for about a week then wish I hadn't stopped!