Funny enough overnight I'd been thinking about the advice and if the situation were reversed. I have been with him since I was 16 and he was 23. I started work at 16 and we moved in together when I was 18. He worked on and off for a few years but I really knuckled down , went to college, got qualified, got promoted and was fairly happy. During this time he wasn't exactly man of the year but I had different priorities and because we had a mortgage just paid what I needed to in order to meet the bills each month. We sold that first house for a massive profit and bought the one we are in today. We used the profit to buy an apartment abroad and a buy to let house nearby. Husband took this as a cue to call himself a 'landlord' and that somehow became is 'job'. He carried on working cash in hand and saved enough for a deposit on the property he bought himself (although as he wasn't contributing to bills/paying mortgage - it was basically half my money anyway). Seriously dysfunctional I know but I'm just be honest I know it makes me look an idiot, but he is very good at arguing and I just don't want to argue. Eventually my parents hit financial difficulties and moved into one of the rentals, just paying the interest on the mortgage to cover costs. Although this caused massive rows between us as he wants to charge them more. He uses this as a way to shut me up if we row saying they can go and find somewhere else to live etc etc.
When girls came along I took 3 and 6 months mat leave (both times went back when full pay stopped) as by then I felt responsible for the upkeep of our lifestyle. My earnings increased significantly when I started consulting 3 years ago and this is when we agreed the £500 allowance arrangement. I did agree too as previously all our money had been eaten up with bills, holidays and him buying flashy cars on finance. As I type this I could slap myself, no wonder he carried on I've been facilitating this for such a long time and going with the flow.
All the time things are ticking along like this it's ok, but any change or disruption to this arrangement and the shit hits the fan. He says he wants to use the rest of my earnings to save for the families future and of course that's my intention too. I just need this to be on my terms.
Other stuff that I started remembering include times he has been violent towards me - a few times over the years, usually when drunk. I gave him an ultimatum after this and it's not happened since, but I do constantly worry when he's been out, he belittles it by saying he had his 'nasty bastard' head on. Unbelievable now I have my eyes open. I also gave up drinking after he told me I had a problem - however I can't see that I actually did. Ridiculous situation. Just another control tactic. He calls me a recovering alcoholic even though I just never had another drink after one occasion when I got so drunk that I didn't remember what happened.
I know he will never change, he's a crap husband, people don't see the full extent (in fact I flippantly call him 'Funtime frankie' when he's out because he is the life and soul). I've got to a point in my life where I can explain it to the kids and move on and I think it's time for the end.
I am scared how he will react, but am prepared to go through it as I think there is still time for me to have a better life. I'm only 44! I've wasted such a lot of time, but am comforted that we have our girls. I'm not bothered about losing out financially I don't want him to be destitute but I am keen there is fairness.
I don't love him anymore apart from the inevitable bond that comes from spending my whole life with him.
I haven't been able to go to a solicitor today as i would have liked because I'm ill in bed with a cold. To give you an insight, he hasn't spoken to me since yesterday mornings argument, he knows I'm struggling in bed and I'm having to get my own drinks and have just walked up the shops to get some Lemsip and tissues. 
Thanks to everyone for taking the time, I'll keep updating as it is giving me the support and turning up the volume of my inner voice. It's obvious what I need to do and I can't even say I didn't know. I did, I just went for the 'easy' option.
Looking back it wasn't so easy after all.