ash turned my blonde hair gray

This is LONG, so thanks for reading :-)

My hair is naturally a medium-light (getting more medium than light as time goes by) ash brown. It was quite blonde until I was about 16 and over time (I'm now 34) it has darkened. In the last two or three years it's also gotten more coarse (esp. after I had a baby almost two years ago).

I used to be able to do all-over color (blonde) myself and get fairly reliable results. I would use a neutral blonde and that's what I got. As my hair has changed, I typically get a strawberry blonde color (i.e. it pulls red). Pretty, but not necessarily what I want.

I had not colored my hair for some time when I had a woman do it for me about six weeks ago. She did an all-over color and sure enough, it pulled red. She assured me that when she did my highlights, it wouldn't show (which is silly, since highlights weave around and would of course leave a lot of the underlying, but whatever). She ended up using too many foils and didn't tone it well, so the color was super golden yellow (with reddish underneath. Ick). My hair did not feel fried, and it behaved well.

But I HATED the color, so I went to an expensive salon (Aveda) to repair it. The woman did get out quite a bit of the yellow, and all of the red, but she insisted on adding lowlights, which I told her would look bad in contrast to the very light hair I ended up with. Sure enough, the lowlights were too low and made my hair look a bit frosted. Still too golden yellow for my taste, too. But it was a good job and so I lived with it. Again, my hair texture felt good and not too dry or fried and it has stayed in nice condition.

SO ... and we're getting to the end, I promise ... I let it go for about six weeks. My darker roots were growing in, and as is common, my hair was turning brassier.

I decided that I would take my chances and dye it myself, this time. I called L'oreal and explained the whole story. I was told that if I wanted to get back to an overall medium blonde, I should use a medium golden blonde times 1.5 (two boxes -- one as normal, plus half the color solution from the second). I balked because I don't want golden blonde hair, but the woman said, "Would you rather have discolored gray? I know you want ash, but an ash dye will turn your hair gray." I almost followed her advice. But when I went to Sally Beauty, they said she was wrong. And my (non pro) intuition said she was wrong, I mean hey, my hair was yellow, so I wanted to add ash.

Well, she was right. So now I have strawberry medium blonde roots, and otherwise grayish-tinted medium tone hair. I wouldn't call it blonde, I wouldn't call it brown. It's the color of a heather gray t-shirt, but not so gray you'd think I was an older woman. Anyway, it sucks. It's not wear-a-hat bad, but it is definitely not pretty. It looks super drab.

I really can't afford and don't trust professionals these days (the last round cost me $300, between the two women). I'd rather take my chances.

Would you:

Put a golden toner in? Is this what "deposit-only" is, and if so, what brand? OR
Use a red-toned shampoo (what brand?)? OR
Do you have other advice?

Please just don't say "see a professional." I know, but I'm in denial.

Thank you so much for reading this whole story and for your time and advice.