if you can't afford the centre, then move a little bit further out - no big deal. my wife and I (+ 2 year old) live in Novena which is actually a great place to be, lots of things to do in the evenings (obviously in the 2 shopping malls) and you get some peace and quiet too. we live in a 3 bed condo and pay 4k/month...which is considered cheap for our place, but you can get some good deals if you hunt around
at work I usually eat at the hawker centres andd food courts, cheap like the budgie and fairly tasty even! travel is by MRT (for me anyway) which is very cheap and my wife takes taxi's here and there during the week, but they're cheap as well really in comparison to the UK for example. we shop at NTUC fairprice and Cold Storage every week, forking out maybe 500 bucks a pop and then we spend about 300 bucks a week on going out, other shopping (we're not really big 'consumers') and we live very comfortably
cost of schooling next year will be tough, but it's around 6k I think for the Tanglin Trust school per term and we're moving close to the school (walking distance) so again, no need for a car which is outrageously expensive here
in short, everything is possible if you're willing to make concessions and move around to help yourselves financially
you don't have to live in Orchard and drive a Porsche Cayenne!
good luck