Now I am just trying to keep my daughter alive.
Is your daughter so low that she's at risk of self harm?
Has she spoken along those lines?
How serious is this?
Twice in your posts you've mentioned 'losing her' and 'keeping her alive'.
Which uni did she go to?
Is she averse to getting in touch and asking for support from their careers advisor?
Have you suggested that to her?
Did she ever work as a teenager? Saturday/ weekend job?
Has she any sporting achievements that show resilience or independence, or any of the 'soft skills' that will give her the edge over other applicants? These need mentioning on her CV.
I'm sure you can appreciate that almost everyone here is saying the same thing- she needs to get out of the house and doing something, mixing with people.
It doesn't matter if it's 3 half days in Caffe Nero, or cleaning an office, or working in a bar- just something.
If she's only been applying for specific marketing roles she will be competing with other grads who've had some work experience etc.
If she's fluent in Spanish she could consider tutoring (GCSE/ A level) online through an agency. Or offering translation services.
Get her to think outside the box.
Also, if she's now registered with agencies, she needs to pester them- the squeaky wheel gets the most attention! If she goes into their offices or calls them every 3-4 days they will respond better.