How can I undo the damage on my hair?

I've been growing out my hair for a while, and its around about 20CM past my shoulders now.

But I straighten it almost every day (I do use heat protection every time I straighten) and I've dyed my hair a LOT. In the past year I've probably dyed it about 6 or 7 times (ah I know. I dye it in the holidays but have to dye it back to my natural colour so my school won't find out, as we aren't allowed to dye our hair)

It's got loads of split ends but I really don't want to have to get it all chopped because I love having long hair and it takes SO long to grow. And I don't particularly like going to hairdressers, because my hair never EVER turns out right lol. Or is there no choice if I want nice soft hair? It feels dry and damaged and just not nice compared to what it was a few years ago.

Help?!

woah 20cm past your shoulders is long, I would never want to cut my hair
if your school doest allow different hair color then they probably wont let you leave it open ryt?
my school was like that
you should leave it the way it is naturally now and then, it would save you time

you rather not color your hair and just wait till you finish school, then you wouldnt waste money by having it for a few weeks and covering it up

you should get a treatment done on your hair, to repair it
go to a salon or drug store

maybe the product that your using isnt good enough
I use pantene repair and protect shampoo and conditioner
and lo'real hot straight heat protection lotion on my hair when I style it
my hair is long and not damaged

hope I helped :-)
take care

I have super curly hair..and I strighten all the time. with no heat protection and I dye my hair... like usually atleast 3 times a month...
and its soft...
I use tresseme conditioner...let it sit on your head
also get queen helen like conditionnig stuff and put it on your head with a shower cap over it...
it will do really good and make your hair look nice

I think you should let your hair go natural for a while. No harmful heat or colouring for at least 1 month. Do weekly deep treatment conditioners to your hair (go to a salon or beauty supply store and ask for the best one for very dry hair). Then when you use it, wrap your hair with a plastic bag and then with a towel to keep your head warm...the heat is really important in the effectiveness of the conditioner. If after a few treatments you find that some areas are still dry, I would suggest to trim them off yourself if you are reluctant to go to the salon. I really think if you do this your hair will be well on its way to repairing itself.