Sounds like you had a lot of bad info from the get go. You can try Jaybird's advice, but I've found that its very hard to erradicate every last living yeast cell, without adding a lot of sorbate & sulphite.
I've always gone with using the right amount of honey in conjunction with a yeast that will attenuate to my final goal (and not have the ability to keep going). Then you can try to stabilize it and backsweeten as necessary.
I've never backsweetened though. With trial and error I've found good methods to produce a mead with some residual sweetness, without being cloyingly sweet/syrupy. With decent body too.
Primary: English Mild
On tap: Pale Ale, Lancelot's Wheat, English Brown Ale, Steam Beer, HoovNuts IPA
Bottled: MOAM, Braggot, Raspberry Melomel, Merlot, Apfelwein, Pyment, Sweet mead, Cabernet
Gal in 2009: 27, Gal in 2010: 34, Gal in 2011: 13, Gal in 2012: 10