You may have just pointed out the problem! I would say that at least a third of cycling is the psycology and desire required to overcome serious obstacles and endure discomfort and pain. If you are doing such a short lap over and over again it must be draining AND you have the 'get out' anytime you are suffering to just go home and give up. Get a lift or a train 110 miles away and ride back - you will have to succeed or pay the price. Also every pedal stroke is one closer to home. The brain is a powerful tool in exercise - use it!
Oh and by the way i use GO BARS, TORQ GELS and JELLY BELLY sports beans. All great products.