I understand your plight man which is one of the reasons I'd encourage people to join the trust. Sadly football in this country has become very overpriced. certainly compared to most other european countries. The Supporters Trust, in conjunction with other trusts, can put pressure on the SPL teams to make it a bit easier for those who can ill afford the costs.
Personally I, and my wife, try and get to as many games as we can, both home and away, and I wouldn't like to try and total the cost over a season but its probably a couple of grand if I count travel, accomodation, refreshments, shirt sponsorship, entrance etc.