Help! Must Decide Color

Hi, I'm new in the forums but I couldn't resist asking for some help. I'm 18 years old and I've been having a stylist color my hair for about the last 3 years. My natural color is a medium brown/light brown. I've gone through highlights to full color. I've always wanted to be an ash blonde.

However, I have not reached that color by any means at all. In fact, on one try, my stylist made my hair orange in an attempt to get my hair blonde. It was a horrible experience going to school with orange hair.

I've been reading a lot on the internet now that in order to reach blonde you must bleach-but it also says that some shouldn't bleach if you've already had your hair colored, is this true?

Also, are there any suggestions as to how I can get an ash blonde? The highlighting these stylists do is a really light blonde rather than a cooler looking blonde.

Please help, I'm getting frustrated to the point where I may just give up on the idea of ash blonde and resort to a darker brown with some golden brown highlights