What to do with years of highlighted hair?

[Tippytoes11]

The hightlights over the years have virtually destroyed my beautiful hair. highlights are Platinum, 8 and 9.
When it is done by the hairdresser, it only looks good on the day.
But when I wash it, it looks like straw and have to put tons of expensive creams and oils from the hair salon. It does not disguise the overprocessed, bleached hair. I avoid blow drying it. I spend so much money for it to look "normal".

I want to disguise grey roots. I do not want to keep my natural greying hair.
Can I put a darker blonde hair (no.7) colour over my highlighted hair or will it turn shades of green?
I don't want to highlight anymore. Should I do the colour myself with box colour or is it too risky?

try a gloss? i have recently used a Wella gloss and it looked good Wella Professionals Color Fresh Mask Temporary Color Refresh Treatment, Semi Permanent Hair Dye, Hair Gloss Treatment for Copper Hair, Caramel Glaze 150ml : Amazon.co.uk: Beauty

I'd go to the hairdresser for a consultation.

Personally I'd ask them to dye my roots the same colour as my natural hair and blend down to break up the blonde, get a toner that's a few shades darker then the platinum, and a good cut and treatment.

I'd then just leave it and get a good at home treatment and just keep getting my roots done/ balayage which is much softer and grows out better.

I've actually just toned down all my blonde to a caramel shade to try and get used to something a bit darker whilst I decide what I want to do.