Hiya Caz,
don't despair about the house. I bought straight away as I got an excellent mortgage deal- if you can see a mortgage advisor most of them will give you a free consultation and help you work out what you can truly afford. The independent ones are better than the banks because a) they don't sell you what you can't afford and b) they have a wider range of products. Once you know how much you can really afford to spend on a house you can set a goal and work towards it.
As for the deposit, that is the hardest bit as you have discovered- it really is a case of scrimping. All your current monthly bills like phone, car insurance etc., shop around, get a cheaper deal, ring them up and tell them you're paying too much. Owning a house is hard and money is always an issue for most people- I ring up my utility providers fairly regularly and push for a better price. This month I've had my landline bill lowered from £50 to £30 a month, and my mobile from £36 a month to £15.50. See what discounts you can get as a teacher, through your union or whatever. They are out there- sometimes to get a discount all you have to do it ask.
My friends are moving to a bigger house. They have had to save save save. One has taken a second job- he works Monday to Friday in his normal job then works every night in a pub behind the bar, and it earns them hundreds more per month. Even a few shifts a month could earn you another £50. Offer to babysit for people- you are a teacher so clearly responsible and experienced with children. What about private tuition? I know you are busy and have long days but at the weekends you could do a few hours private tuition for a little extra cash. This goes for Aaron too, I don't know what he does for a living but can he take a second job?
I scrimp and buy the cheapest I can find so that I can afford to do things, pay my bills etc. You won't find any brand names in my house
Sorry if this is teaching you to suck eggs, but I have been there and if you look at every option it is sometimes more achievable than you think.