battery light keeps coming on. truck dies once a week

This problem has occured about 4 times so far. The battery light will often come on. I replaced the alternator 3,000 miles ago. I put a brand new battery in it 300 miles ago. I have put too much money in it to make a profit in selling it. A lead running from the negative battery cable to the inner fender broke. It was replaced and the problem just re occured today( 2-17-16 ). If anyone can help please let me know.