How old are you?

Sometimes you just have to deal with things and look for other ways. For instance:
Get a second job.
Work more hours at the LBS
Ask if the LBS would help you out with a discount
Ask the LBS if you could take the bike now and they'll deduct it from your pay
Go to someone else other than MOM, grandparents, Dad, Brother, Sister
Buy a used bike. Many good values since some people fall on hard times and need to sell theirs. Ebay, newspaper etc.

Sounds to me that for someone who so good academically you need a little common sense, and stop blaming everyone else for your lack of imagination.