I constantly bite my nails and I've been doing it for over 15 years now 
I can't stop!
I've tried that nasty tasting polish on my nails, and I still bite them. I can keep nail polish on my nails for a little while (but it looks terrible because my nails are so short right now), but as soon as one nail chips I start picking and biting at the rest of my nails. I had gel nails for a little while, but I eventually started playing with them and managed to damage a nail and bite it off. I'd get gel nails again, but I can't always wear them (due to sports) so I'd always be getting them and taking them off a few months later. I've read articles about the germs under your nails and that still doesn't turn me off.
I bite them until it hurts and they look terrible. Some of the nails have deformed from ripping off the nail so far.
The problem is that I don't even realize when I'm biting my nails. I'm doing it a lot at work now, and the only way I can stop is by eating constantly (which isn't a good thing either). Even if I'm chewing gum I'll bite a nail if it's really bothering me.
I don't know what else to do because I feel like I've tried everything! I want nice, pretty nails! Please help!
Thank you if you read all this!

I can't stop!
I've tried that nasty tasting polish on my nails, and I still bite them. I can keep nail polish on my nails for a little while (but it looks terrible because my nails are so short right now), but as soon as one nail chips I start picking and biting at the rest of my nails. I had gel nails for a little while, but I eventually started playing with them and managed to damage a nail and bite it off. I'd get gel nails again, but I can't always wear them (due to sports) so I'd always be getting them and taking them off a few months later. I've read articles about the germs under your nails and that still doesn't turn me off.
I bite them until it hurts and they look terrible. Some of the nails have deformed from ripping off the nail so far.
The problem is that I don't even realize when I'm biting my nails. I'm doing it a lot at work now, and the only way I can stop is by eating constantly (which isn't a good thing either). Even if I'm chewing gum I'll bite a nail if it's really bothering me.
I don't know what else to do because I feel like I've tried everything! I want nice, pretty nails! Please help!
Thank you if you read all this!