It's all relative though.
Our mortgage repayments are have of yours but I would bet our house is likely half the size too (115m2), or yours is in a much better location (our is right out on the edge of town - literally go the bush across the road).
Only 115? Yikes! Our little worker's cottage is about 90sqm, plus verandahs. No wonder you're squeezy. My old house and the new one we are building are both 150sqm (plus verandahs) but one has massive bedrooms, one massive bathroom, and the new one is a modern layout with smaller bedrooms, more bathrooms, walk in robe etc but heaps of living area. All the builders have a floorplan very very similar to our new house, and it is our builder's most popular 4br design - very good value for money.

Rumpled elf may have significantly cheaper mortgage then myself, but I bet her household income is alot less too.
Centerlink give me $320 a fortnight while I'm too pregnant to work! I feel so rich! And the builder wants us to get loan approval 6+ months before they even start the house while our mortgage broker is trying to negotiate us getting a loan AFTER the house is built. Argh. This is what you get for building a transportable - costs $60k less than the equivalent house built onsite in brick, but much harder to get a loan for. All fun and games.