Wow, that's a lot of replies.
I'll try to clarify.
My husband is very high ranking and whilst this is good financially it's means he is often called into work at a moments notice and rarely leaves on time. His work is very inflexible but it's just the nature of the beast.
When we had children I initially changed to part time work but when our second came along we jointly decided i would be a sahm. There is no "leaving it all to the mother" mentality here, it's just his job paid more and made sense that I stayed home. We're surely not the only family for whome this was the case.
I'm quite content being a sahm, as is my husband. He retires in a decade with a very good pension so we're not looking at working till I'm 60 plans. Even if he was to die, or leave I'm still entitled to his pension. Not that we intend that 
I am thinking about working as I feel it could benefit me. However I'm not stuck at home, I run a club & have a very active life. Just sometimes miss working, I'm not 100% sure I want to work but I'm giving it thought hence my child care investigations. DH had said he'll support me whatever & we'll make it work, but as I say, the nature of his job means it would fall to me mainly to sort kids. He works shifts all over the clock, sometimes doesn't even make it home. It's not unusual for a terrorist attack for example to mean he works 24 hours straight, just is what it is.
Childcare is expensive. Breakfast club is £7 per child per day, after school is £13.50 per child per day. Holiday club £33 per child per day. Sibling discount is 10%. Child minders are few and far between here with availibilty. (And I couldn't be a child minder myself, no offence to those who are I just couldn't do it. Plus if DH on nights it's awkward). I have no family or friends to help & DH only gets 21 days leave. I doubt I'd get much more, but we could work it between us.
I would never ask my kids to give up their clubs, they enjoy them. It wouldn't be fair and that's that.
£66k sure sounds a lot right. Doesn't go far down London way believe me, and his pension is high contributions as that's what is set in his force. Reducing would make minimal difference. We are comfortable, but not splurging if that makes sense.
I feel guilty that he works so hard, and I don't financially contribute. He doesn't see it this way, says I work harder than he does and likes that I'm around for all the school stuff (as do i) but equally understands if I want to work.
But with a decade of work ahead before we private pension off, I'm looking for a job that financially makes sense, doesn't cramp family life too much especially given my husband's work, and that I can do. Maybe it's all a bit pipe dreamy, I don't know. Maybe deep down I don't want to work, or maybe I do??
I can't be the only mother to have had these thoughts right?