I just replaced the fuel pump on my son's 2001 Ford Focus, 44,000 miles. I've researched the problem with these pumps and from viewing the pump I pulled out of his Focus, its clear the problem is the contamination from fuels clogging up the pickup strainers to the pump, there for straining the pump and causing it to fail. The relay usually kicks it off, but over time the heat and strain put on the pump will cause it to fail. There are two strainers on the pump, the sock is clearly the item clogging. Wether this is from bad fuels or the filtering property of the sock is unknown.
I went to auto dismanterler and purchased a used pump for $59. with 90 day warranty. It too had a severely contaminated pickup sock on it. I cleaned it and installed the pump. The Vehicle works great now and my son has returned my Ford explorer to me...in one piece.
The pump on the Ford Focus is the same basic pump installed on 80% of ALL vehicles onthe road. Being a ASE technician, its it only my opinon that the problem might be with the cheap fuels being used, or the pickup sock on the pump. Majority of the fuel tanks I've pulled over the years, there is no contamination and these vehicles had 100,000+ miles on them, except for this Focus. Good luck!!