hi again Dillinger. on the half - if you can do 5 now then you can definitely do a half in March. but imho you need to commit to a scedule now-ish. I guess that means agreeing with dh and other commitments etc on when you have time to run - I find that if I have 1 or 2 regular days then I can switch a third one about depending on what else is happening that particular week - but I find it hard to get out if I take the flexible switching approach with all my runs - if that makes sense. But that's me and everyone's different. But I do find it incredibly helpful to have a schedule (goodrunguide.co.uk is great for that - you can put your planned runs on a calendar and then put your actual runs on it).
having said all that - with kids etc I've found my running going in big troughs and peaks - and if you sit down and realise that you realistically can't fit in a half marathon schedule right now then don't be disappointed - your kids are still very young, and in 6 months, or a year or 2 everything will have changed - in terms of nursery, school etc, and you may find more time then. (or you may find a september half when you would have light evenings in which to train would suit you better)
re confidence etc - the joy of running - which, imo, all runners, however good they are, realise, is that it's such an open sport. you don;t need to be super co-ordinated, you don;t need to be super athletic or fast. you just need to be able to put one foot in front of the other and enjoy your own, functioning, body. you don;t need to be at a particular standard, you don;t need to compete with other people, you set your own goals, (or you don't, if you prefer!), you set your own pace. it's at once an intensely personal sport and one that has a shared joy. so try to relax and enjoy it for what it is.