Hair DISASTER..helpp!

alright well about 2 years ago i first dyed my hair. my natural hair color was a dark dark brown, and i was looking to dye it reddish and so my aunt went to the store, bought an ashy blonde and a reddish and went home and mixed both of them together. she dyed my hair and i discovered it to be a subtle orange color. AT THE TIME i liked it, so i kept it for about a year. during that time i was taking swimming lessons, so i had gotten a lot of chlorine and stuff in my hair. later the next year i decided i want my original color back so my mom tried dying it back to dark brown (she used permanent dye). that lasted about a month, then the tips faded to orange. we kept dying my hair every 4 months a PERMANENT dark dark brown color but it kept on fading. last year, i actually went to a supercuts and had my hair dyed a dark dark mahogany. now my hair is like 2 shades. the top is like dark brown, and the middle of my hair down is orange and red. i had to be in the sun, because all the red and orange shows through & looks totally unnatural. now i have NO IDEA what to do because i want a PERMANENT dark brown or black color to stay in my hair forever and NOT fade back, but everyones been telling me the same thing my hair is damaged and i cant do anything about it except cut the faded parts out. and thats a lot of my hair cuz my hair is long...so im really at a crossroads here...i hate this color but i dont wanna keep dying it and have it fade back again. any ideas?? pleaseee help!! thank youu!