TradeSkills4U do courses for ex military (discounts!). There were two ex-army guys on the course I completed last year. Also, don't listen to all the negativity you find on some forums, it's amazing what a determined man can achieve in a short time. Compare a man with a family and a mortgage with a 19 year old apprentice who's only interested in booze, drugs, cars and sex, then you'll see how fast an old dog can learn new tricks!
I was made redundant in November 2016, I went to TradeSkills4U and completed their C&G2365 course (16 weeks in the class room spread over 32 weeks). At the same time as doing the course I started work with a local electrical contractor - I tried offering myself for free but they insisted on paying, which was nice, but it wasn't much money. I stayed with them gaining experience after I finished the course. I spent a lot of time being subcontracted to a local factory and when a position came up there (the factory) for a permanent electrician I applied, even though I don't yet have my NVQ3, I recently started there as an electrician on £40K/year. Lots of holiday, sick pay, pension, on-going training, and great working environment. Another guy on the same course as me is working in London as a mate for £180/day, with the experience he's getting he'll have enough evidence for his portfolio and will have his NVQ and gold card by Christmas. Rates at the 23 Bishop's Gate dev (where he's working) are in the region of £230/day for sparks.
To get work I don't think you've contacted enough companies. I used the 'find an electrician' section of the NICEIC website, I skipped all 'domestic installers', and copied the addresses of > 140 companies. I used a mail-merge program to send them all a personalised letter ("Dear [company name]"), I had about 40 responses, most were "thank you but sorry....", about 12 were "keep in touch we might....", and 5 were looking for someone, I interviewed with two (after checking them out on-line - didn't want to waste my time with 2-bit cowboys). If you can't work the mail-merge part of MS Office yourself find someone who can, there's no way you'll write 140 letters without it, and you need to mail a lot to get some response. Also, send an SAE with each letter, the recipient will know you're serious the more effort you put in.
Good luck, and don't give up, it's a lot of hard work, and the harder you work the sooner you'll get there - Oh, and don't stop asking questions of the seasoned pros!