Q. I have been applying for jobs for several months.
I have not been shortlisted for some jobs that I thought, from reading the job description, would be perfect for me. I have worked very hard on my CV and I only apply for jobs that area good match for my skills and abilities, but I feel that my slightly less traditional background may be holding me back.
A. You attached your CV and letter of application, and I can see that your less traditional background is indeed likely to be holding you back, primarily because that is the main thing that you mention and then try to explain away in your cover letter.
Remember that when employers go through a stack of CVs to shortlist, they are looking for the easy ones to say "yes" or "no", and then if they are short on "yes" candidates they may look at ones that are in-between. Your cover letter makes you look more like a "no" or "maybe" than a "yes", even though your CV may match the job requirements.
Instead of focusing on your non-traditional career path, outline how (and how well!) your skills and abilities match the requirements of the job. If potential employers can see that you have considered the job requirements and can set out a clear match, they will read your CV in a more positive light, and you'll be much more likely to get to the interview stage.
Don't dwell on your career history in the interview, either.
If you think you may be asked about it, think carefully about the skills and abilities developed in your career history that will be applied in this job.