Well I am assuming you have all your finances in order, no debt, emergency funds, retirement funds, and the issue is not the money.

In any case, a bike is more like an investment in your future. Riding a bike regularly is way cheaper than, say, a heart attack.

I can't help but wonder if this really isn't some sort of a control issue. In which case you have much deeper problems to deal with. Perhaps Crankin will chime in here.