You are going to need to cut it. It's dead. Go see your hair stylist.
But, deep conditioners are good to help your hair when you do bleach/hair dye in general. If it's frizzy and straw like, however, it's most likely not fixable. You cannot fix split ends/dead hair.
I use Aussie Three Minute Mineral deep conditioner. It apply it in the shower after I shampoo, tie it up in a very loose bun on the top of my head, finish whatever else I need to do in the shower (shave, wash face, wash body, whatever), then the last thing I do is rinse out the conditioner. Use this once a week, twice if you feel that you really need it. Sometimes, I'll mix a little into my normal conditioner just to bump up the power of my normal one. Don't over rinse, and do not wash your hair every day. Use a gentle leave-in-conditioner when you get out of the shower, and use a wide tooth comb to get the tangles out gently. Let it dry naturally if you can. Try not to use heat on it, tease it or use a lot of product in it to help it heal and grow out some. Let it just do it's thing. Gently tie it back into a low, not too tight pony tail/bun/braid when you go out so it doesn't get whipped around in the wind and damaged and tangled and horrible. Don't use bleach or dye for a while (a month would be good for dye; longer for bleach). Get a trim every 8 weeks or so to help keep your ends fresh. If you wait too long, your ends will split even higher, meaning more to cut off.