Thank you everyone for your advice. I really appreciate it, and love how caring this place is.
To all those suggesting that she go see a doctor, I think that others are right saying that she shouldn't go. it might be a step too far, and the suggestion of a book I think would be great, as long as I can get her to read it. She has agreed to get a book to help her, and I have found one for helping people with depression that I'll read to get some advice. Hopefully they will be beneficial.
I'm also going to encourage her to exercise more. We actually both started running together this week, and we both really enjoyed it, so I'll encourage that more. We also play badminton together with her sister and her fiancé occasionally, so I'll try and get her doing more of that too.
With regards to work, I don't think she could stomach forensic clean up! I wouldn't want her to do that sort of job, to be honest. I know it's anecdotal, but my uncle was in the police for many years and saw a lot of horrible things. He went on to suffer manic depression and killed himself...I'd rather she wasn't exposed to that! Good luck to you though, sounds very lucrative if you can stomach it.
I will suggest that she does some sort of CBT, or at least get a book that for her that works on that basis, so thank you for that suggestion.
RedvGreen, I'll email you later. Thank you very much
Sports_brah, thank you. I think you've hit the nail on the head - very perceptive! She definitely feels that everyone else's lives around her are steaming ahead and that she's being left behind

I think she just needs to be patient, but it can't be fun sitting at home all day mulling it over as she is now. I really wish she could find the right job for her skills, but I feel she's been looking at the wrong kind of thing, - desk jobs, when she's more creative than that.
To those that have spoken against medication, that's also not the route that I'd like her to take. I think she needs a confidence boost really, but I'm not sure how I can provide her with that. I do my best to encourage her, tell her I'm proud of her etc, but I think that she thinks that I'm taking the ****.
I'm encouraging her to embrace this business idea, but it hasn't got off to the start she hoped. I read somewhere though that people who are self depreciating tend to react negatively to you telling them that they're doing really well at something and that it's much better to tell them that no matter what happens, everything is a learning experience. I tried this and it actually works to some extent!!
To those that have recommended books, I'll look them up and hopefully get her one soon. I'm so surprised, and so glad, that she actually entertained the idea of reading one! Part of the problem is that she knows she needs to sort this out, and acknowledges that she's depressed, but always wants a quick fix. We all know there isn't one though.
Once again, thank you all. This community is fantastic.