MTT are doing my head in

Just finished the $35,000gtd on Full tilt and I just can't get across the finishing line.
1433 runners... chip leader with 90 to go and crash out again in 52nd.
This is totally doing my head in as I really don't know how I can't win.
Don't know if I'm too agressive or what I'm doing wrong but $7,500 for first and bullshit $72 for 50th, I just don't know how much longer I can deal with this.
I'd do anything to give up this game but it pays the bills, and I also know that I'm just a hand or two away from winning something decent. I really take my hat of to all you guys that play these for a living because its either all or nothing in them. I've done about 16hrs today and I'm sitting here at 5.30am looking at another tourny starting in 30min..This is one sick life.